{"appState":{"pageLoadApiCallsStatus":true},"articleState":{"article":{"headers":{"creationTime":"2017-05-01T01:05:35+00:00","modifiedTime":"2017-05-01T01:05:35+00:00","timestamp":"2022-09-14T18:18:39+00:00"},"data":{"breadcrumbs":[{"name":"Academics & The Arts","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33662"},"slug":"academics-the-arts","categoryId":33662},{"name":"Teaching","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33800"},"slug":"teaching","categoryId":33800},{"name":"Skills Tests","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33806"},"slug":"skills-tests","categoryId":33806},{"name":"Praxis","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33807"},"slug":"praxis","categoryId":33807}],"title":"Practice Math Questions for Praxis: Solving Expressions with Given Values","strippedTitle":"practice math questions for praxis: solving expressions with given values","slug":"practice-math-questions-praxis-solving-expressions-given-values","canonicalUrl":"","seo":{"metaDescription":"Some questions on the Praxis Core exam involve a simple plug-and-play approach, where you solve an expression by substituting given values for the variables. So","noIndex":0,"noFollow":0},"content":"Some questions on the Praxis Core exam involve a simple plug-and-play approach, where you solve an expression by substituting given values for the variables. Sounds easy, right?\r\n\r\nWell, yes and no: as you'll see in the following practice questions, you still need to watch out for double negatives and you have to know your order of operations.\r\n<h2 id=\"tab1\" >Practice questions</h2>\r\n<ol>\r\n\t<li>What is the value of this expression if <em>x</em> = 1, <em>y</em> = –5, <em>z</em> = 8?\r\n\r\n7<em>x</em> – 5<em>y</em> + 4<em>z</em>\r\n\r\n<strong>A.</strong> –8\r\n<strong>B.</strong> 103\r\n<strong>C.</strong> 64\r\n<strong>D.</strong> 36\r\n<strong>E.</strong> –71</li>\r\n\t<li>What is the value of this expression if <em>k</em> = –7, <em>m</em> = –10, and <em>n</em> = 11?\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1801.gif\"><img class=\"alignnone wp-image-238996 size-full\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1801.gif\" alt=\"PRAXIS_1801\" width=\"107\" height=\"340\" /></a></li>\r\n</ol>\r\n<h2 id=\"tab2\" >Answers and explanations</h2>\r\n<ol>\r\n\t<li>The correct answer is Choice <strong>(C).\r\n\r\n</strong>Substitute each variable value in for its corresponding variable. Then simplify the result.\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1802.gif\"><img class=\"alignnone size-full wp-image-238997\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1802.gif\" alt=\"PRAXIS_1802\" width=\"229\" height=\"103\" /></a></li>\r\n\t<li>The correct answer is Choice <strong>(C).\r\n\r\n</strong>You can substitute each variable value in for its corresponding variable and then simplify the resulting rational expression:\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1803.gif\"><img class=\"alignnone wp-image-238998 size-full\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1803.gif\" alt=\"PRAXIS_1803\" width=\"279\" height=\"452\" /></a></li>\r\n</ol>","description":"Some questions on the Praxis Core exam involve a simple plug-and-play approach, where you solve an expression by substituting given values for the variables. Sounds easy, right?\r\n\r\nWell, yes and no: as you'll see in the following practice questions, you still need to watch out for double negatives and you have to know your order of operations.\r\n<h2 id=\"tab1\" >Practice questions</h2>\r\n<ol>\r\n\t<li>What is the value of this expression if <em>x</em> = 1, <em>y</em> = –5, <em>z</em> = 8?\r\n\r\n7<em>x</em> – 5<em>y</em> + 4<em>z</em>\r\n\r\n<strong>A.</strong> –8\r\n<strong>B.</strong> 103\r\n<strong>C.</strong> 64\r\n<strong>D.</strong> 36\r\n<strong>E.</strong> –71</li>\r\n\t<li>What is the value of this expression if <em>k</em> = –7, <em>m</em> = –10, and <em>n</em> = 11?\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1801.gif\"><img class=\"alignnone wp-image-238996 size-full\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1801.gif\" alt=\"PRAXIS_1801\" width=\"107\" height=\"340\" /></a></li>\r\n</ol>\r\n<h2 id=\"tab2\" >Answers and explanations</h2>\r\n<ol>\r\n\t<li>The correct answer is Choice <strong>(C).\r\n\r\n</strong>Substitute each variable value in for its corresponding variable. Then simplify the result.\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1802.gif\"><img class=\"alignnone size-full wp-image-238997\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1802.gif\" alt=\"PRAXIS_1802\" width=\"229\" height=\"103\" /></a></li>\r\n\t<li>The correct answer is Choice <strong>(C).\r\n\r\n</strong>You can substitute each variable value in for its corresponding variable and then simplify the resulting rational expression:\r\n\r\n<a href=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1803.gif\"><img class=\"alignnone wp-image-238998 size-full\" src=\"https://www.dummies.com/wp-content/uploads/PRAXIS_1803.gif\" alt=\"PRAXIS_1803\" width=\"279\" height=\"452\" /></a></li>\r\n</ol>","blurb":"","authors":[{"authorId":9383,"name":"Carla Kirkland","slug":"carla-kirkland","description":"","hasArticle":false,"_links":{"self":"https://dummies-api.dummies.com/v2/authors/9383"}},{"authorId":9384,"name":"Chan Cleveland","slug":"chan-cleveland","description":" <p><b>Carla C. Kirkland</b> is CEO of The Kirkland Group, a consulting firm providing professional development, technical assistance, and standardized test preparation to schools. <b>Chan Cleveland,</b> Executive Vice President of The Kirkland Group, has created and revised language arts standards for many school districts. ","hasArticle":false,"_links":{"self":"https://dummies-api.dummies.com/v2/authors/9384"}}],"primaryCategoryTaxonomy":{"categoryId":33807,"title":"Praxis","slug":"praxis","_links":{"self":"https://dummies-api.dummies.com/v2/categories/33807"}},"secondaryCategoryTaxonomy":{"categoryId":0,"title":null,"slug":null,"_links":null},"tertiaryCategoryTaxonomy":{"categoryId":0,"title":null,"slug":null,"_links":null},"trendingArticles":null,"inThisArticle":[{"label":"Practice questions","target":"#tab1"},{"label":"Answers and explanations","target":"#tab2"}],"relatedArticles":{"fromBook":[{"articleId":239134,"title":"Practice Math Questions for Praxis: Pyramids","slug":"practice-math-questions-praxis-pyramids","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"_links":{"self":"https://dummies-api.dummies.com/v2/articles/239134"}},{"articleId":239130,"title":"Practice Math Questions for Praxis: Cones","slug":"practice-math-questions-praxis-cones","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"_links":{"self":"https://dummies-api.dummies.com/v2/articles/239130"}},{"articleId":239125,"title":"Practice Math Questions for Praxis: Cylinders","slug":"practice-math-questions-praxis-cylinders","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"_links":{"self":"https://dummies-api.dummies.com/v2/articles/239125"}},{"articleId":239121,"title":"Practice Math Questions for Praxis: Prisms","slug":"practice-math-questions-praxis-prisms","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"_links":{"self":"https://dummies-api.dummies.com/v2/articles/239121"}},{"articleId":239090,"title":"Practice Math Questions for Praxis: Similar and Congruent 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Test","slug":"visual-and-quantitative-information-questions-on-the-praxis-reading-test","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"_links":{"self":"https://dummies-api.dummies.com/v2/articles/268426"}}]},"hasRelatedBookFromSearch":false,"relatedBook":{"bookId":282493,"slug":"praxis-core-1001-practice-questions-for-dummies","isbn":"9781119263883","categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"amazon":{"default":"https://www.amazon.com/gp/product/1119263883/ref=as_li_tl?ie=UTF8&tag=wiley01-20","ca":"https://www.amazon.ca/gp/product/1119263883/ref=as_li_tl?ie=UTF8&tag=wiley01-20","indigo_ca":"http://www.tkqlhce.com/click-9208661-13710633?url=https://www.chapters.indigo.ca/en-ca/books/product/1119263883-item.html&cjsku=978111945484","gb":"https://www.amazon.co.uk/gp/product/1119263883/ref=as_li_tl?ie=UTF8&tag=wiley01-20","de":"https://www.amazon.de/gp/product/1119263883/ref=as_li_tl?ie=UTF8&tag=wiley01-20"},"image":{"src":"https://www.dummies.com/wp-content/uploads/praxis-core-1001-practice-questions-for-dummies-cover-9781119263883-204x255.jpg","width":204,"height":255},"title":"Praxis Core: 1,001 Practice Questions For Dummies","testBankPinActivationLink":"","bookOutOfPrint":false,"authorsInfo":"<p><b data-author-id=\"10794\">Carla Kirkland,</b> founder and CEO of the Kirkland Group, an educational consulting firm, has helped educators prepare their students for standardized tests for more than 20 years.</p> <p><b data-author-id=\"9384\">Chan Cleveland,</b> executive vice president of the Kirkland Group, is an English educator who has developed language arts resources for multiple school districts.</p>","authors":[{"authorId":10794,"name":"Carla C. Kirkland","slug":"carla-c-kirkland","description":" <p><b>Carla C. Kirkland</b> is CEO of The Kirkland Group, a consulting firm providing professional development, technical assistance, and standardized test preparation to schools. <b>Chan Cleveland,</b> Executive Vice President of The Kirkland Group, has created and revised language arts standards for many school districts. ","hasArticle":false,"_links":{"self":"https://dummies-api.dummies.com/v2/authors/10794"}},{"authorId":9384,"name":"Chan Cleveland","slug":"chan-cleveland","description":" <p><b>Carla C. Kirkland</b> is CEO of The Kirkland Group, a consulting firm providing professional development, technical assistance, and standardized test preparation to schools. <b>Chan Cleveland,</b> Executive Vice President of The Kirkland Group, has created and revised language arts standards for many school districts. 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Sounds easy, right?\r\n\r\nWell, yes and no: as you'll see in the following practice questions, you still need to watch out for double negatives and you have to know your order of operations.\r\nPractice questions\r\n\r\n\tWhat is the value of this expression if x = 1, y = –5, z = 8?\r\n\r\n7x – 5y + 4z\r\n\r\nA. –8\r\nB. 103\r\nC. 64\r\nD. 36\r\nE. –71\r\n\tWhat is the value of this expression if k = –7, m = –10, and n = 11?\r\n\r\n\r\n\r\nAnswers and explanations\r\n\r\n\tThe correct answer is Choice (C).\r\n\r\nSubstitute each variable value in for its corresponding variable. Then simplify the result.\r\n\r\n\r\n\tThe correct answer is Choice (C).\r\n\r\nYou can substitute each variable value in for its corresponding variable and then simplify the resulting rational expression:\r\n\r\n\r\n","item_vector":null},"titleHighlight":null,"descriptionHighlights":null,"headers":null,"categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"title":"Practice Math Questions for Praxis: Solving Expressions with Given Values","slug":"practice-math-questions-praxis-solving-expressions-given-values","articleId":238995},{"objectType":"article","id":239001,"data":{"title":"Practice Math Questions for Praxis: Solving Algebraic Expressions Using Substitution","slug":"practice-math-questions-praxis-solving-algebraic-expressions-using-substitution","update_time":"2017-05-01T01:12:48+00:00","object_type":"article","image":null,"breadcrumbs":[{"name":"Academics & The Arts","slug":"academics-the-arts","categoryId":33662},{"name":"Teaching","slug":"teaching","categoryId":33800},{"name":"Skills Tests","slug":"skills-tests","categoryId":33806},{"name":"Praxis","slug":"praxis","categoryId":33807}],"description":"When you're asked to solve an algebraic problem—for example, a system of equations—on the Praxis Core exam, start by checking the variables. If you can easily isolate one of them, then you can probably use substitution.\r\n\r\nIn the following practice questions, you start by performing a simple substitution within a rational algebraic expression; then, you go a little deeper by performing a more complex substitution to solve for two variables.\r\nPractice questions\r\n\r\n\tIf w = y, what is the value of\r\n\r\n\r\n\tIf 2x + 4y = 32 and x – 2y = –12, which of the following is true?\r\n\r\nA. x + y = 10\r\nB. 5x – y = 3\r\nC. 8x + y = 26\r\nD. 3x – 2y = –11\r\nE. x – y = –2\r\n\r\nAnswers and explanations\r\n\r\n\tThe correct answer is Choice (D).\r\n\r\nBecause w and y have the same value, you can substitute one in for the other and work with only one variable, which allows for cancelations:\r\n\r\n\r\n\tThe correct answer is Choice (B).\r\n\r\nYou can use elimination or substitution to solve for x or y. Substitution might be easier because in the second equation, you can easily isolate the x because it doesn't have a written coefficient (and neither variable has two coefficients with the same absolute value, which would be ideal for elimination). To use that method, solve the second equation for x in terms of y:\r\n\r\n\r\n\r\nNext, substitute –12 + 2y in for x in the other equation, 2x + 4y = 32. You'll then be working with an equation with one variable, and an equation with one variable can be solved.\r\n\r\n\r\n\r\nNow that you know y has a value of 7, you can put 7 in for y in either given equation to find x:\r\n\r\n\r\n\r\nTo check your answer, you can put 2 in for x and 7 in for y in the given equations and see that the pair makes both equations true. Next, test each of the choices to see which one is made true by the pair. The only one it works for is Choice (B).\r\n","item_vector":null},"titleHighlight":null,"descriptionHighlights":null,"headers":null,"categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"title":"Practice Math Questions for Praxis: Solving Algebraic Expressions Using Substitution","slug":"practice-math-questions-praxis-solving-algebraic-expressions-using-substitution","articleId":239001},{"objectType":"article","id":238989,"data":{"title":"Practice Math Questions for Praxis: Simplifying an Algebraic Expression","slug":"practice-math-questions-praxis-simplifying-algebraic-expression","update_time":"2017-05-01T00:58:25+00:00","object_type":"article","image":null,"breadcrumbs":[{"name":"Academics & The Arts","slug":"academics-the-arts","categoryId":33662},{"name":"Teaching","slug":"teaching","categoryId":33800},{"name":"Skills Tests","slug":"skills-tests","categoryId":33806},{"name":"Praxis","slug":"praxis","categoryId":33807}],"description":"Some algebraic expressions on the Praxis Core exam may look intimidating, and you may even want to give up on them and move on. As you'll see in the following practice questions, though, you can use some simple techniques—like factoring and combining like terms—to solve them.\r\nPractice questions\r\n\r\n\tWhich of the following is the simplified form of the expression 8x2y – 5xy2 + 12xy2 – 3x2y?\r\n\r\nA. 5x2y2 + 7x2y\r\nB. 3x2y + 9xy2\r\nC. 5x2y + 7xy2\r\nD. 5x2y2 + 7x2y2\r\nE. 7x2y2 + 5x2y2\r\n\tWhich of the following is the simplified form of\r\n\r\n\r\n\r\nAnswers and explanations\r\n\r\n\tThe correct answer is Choice (C).\r\n\r\nYou can combine the like terms to simplify the expression. Like terms have the same variables, and each variable has the same exponent in each of the like terms.\r\n\r\nTo combine like terms, add their coefficients; the variable-and-exponent combinations that the terms have in common go to the right of the new coefficients:\r\n\r\n\r\n\tThe correct answer is Choice (D).\r\n\r\nFactor the numerator and denominator. Then cancel any expression that's a factor of the numerator and denominator.\r\n\r\n\r\n","item_vector":null},"titleHighlight":null,"descriptionHighlights":null,"headers":null,"categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"title":"Practice Math Questions for Praxis: Simplifying an Algebraic Expression","slug":"practice-math-questions-praxis-simplifying-algebraic-expression","articleId":238989},{"objectType":"article","id":239049,"data":{"title":"Practice Math Questions for Praxis: Solving Functions","slug":"practice-math-questions-praxis-solving-functions","update_time":"2017-05-01T02:49:49+00:00","object_type":"article","image":null,"breadcrumbs":[{"name":"Academics & The Arts","slug":"academics-the-arts","categoryId":33662},{"name":"Teaching","slug":"teaching","categoryId":33800},{"name":"Skills Tests","slug":"skills-tests","categoryId":33806},{"name":"Praxis","slug":"praxis","categoryId":33807}],"description":"If you enjoy solving functions (and why wouldn't you?), then you'll have a great time on the Praxis Core exam. The following practice questions will help you put the fun into \"function\" by asking you to first solve a simple function, and then to find the value of two functions combined!\r\nPractice questions\r\n\r\n\tIf f(x) = x – 2, what is the value of f(3)?\r\n\r\nA. 1\r\nB. 4\r\nC. 3\r\nD. 0\r\nE. 2\r\n\tFor the two following functions, what is the value of f(g(1))?\r\n\r\nf(x) = 8x2 – 2x + 12\r\n\r\ng(x) = 3x + 5\r\n\r\nA. 508\r\nB. 415\r\nC. 29\r\nD. 580\r\nE. 18\r\n\r\nAnswers and explanations\r\n\r\n\tThe correct answer is Choice (A).\r\n\r\nBecause f(3) replaces the x in f(x) with 3, put 3 in for x in x – 2:\r\n\r\n\r\n\tThe correct answer is Choice (A).\r\n\r\nFirst, find the value of g(1):\r\n\r\n\r\n\r\nBecause g(1) is 8, f(g(1)) is f(8):\r\n\r\n\r\n\r\nTherefore, f(g(1)) is 508, Choice (A).\r\n","item_vector":null},"titleHighlight":null,"descriptionHighlights":null,"headers":null,"categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"title":"Practice Math Questions for Praxis: Solving Functions","slug":"practice-math-questions-praxis-solving-functions","articleId":239049},{"objectType":"article","id":239019,"data":{"title":"Practice Math Questions for Praxis: Solving Systems of Equations","slug":"practice-math-questions-praxis-solving-systems-equations","update_time":"2017-05-01T01:31:49+00:00","object_type":"article","image":null,"breadcrumbs":[{"name":"Academics & The Arts","slug":"academics-the-arts","categoryId":33662},{"name":"Teaching","slug":"teaching","categoryId":33800},{"name":"Skills Tests","slug":"skills-tests","categoryId":33806},{"name":"Praxis","slug":"praxis","categoryId":33807}],"description":"Some problems on the Praxis Core exam will involve systems of equations. Although they look intimidating, they're actually pretty straightforward to solve if you take the right approach.\r\n\r\nIn the first practice question, you're given two simple equations, and you have to find the solution to the system of equations using elimination. In the second question, you have to use substitution to solve a system of equations, and then answer a separate question based on the values of x and y.\r\nPractice questions\r\n\r\n\tIf 2x + 6y = 58 and 5x + 2y = 41, what is the solution to the system of equations?\r\n\r\nA. (8, 5)\r\nB. (5, 3)\r\nC. (–8, 5)\r\nD. (4, –3)\r\nE. (5, 8)\r\n\tIf x + 2y = 22 and 7x – 3y = 1, which of the following numbers is NOT between the values of x and y?\r\n\r\nA. 6\r\nB. 8\r\nC. 5\r\nD. 3\r\nE. 7\r\n\r\nAnswers and explanations\r\n\r\n\tThe correct answer is Choice (E).\r\n\r\nYou can use substitution to solve this system of equations, but elimination is easier. You need to multiply one of the equations by a number that allows you to line up coefficients with the same absolute value for one variable. If you multiply the second equation by –3, you can get the y terms to cancel:\r\n\r\n\r\n\r\nThen you can solve for x:\r\n\r\n\r\n\r\nYou can put 5 in for x in either original equation (or any equation derived from them with both variables) to determine the value of y:\r\n\r\n\r\n\r\nThe solution is therefore (5, 8). Remember that in an ordered pair, the first number represents x or whichever other variable comes first alphabetically. You can put that solution into any of the equations with both variables and see that it works. None of the other choices work.\r\n\tThe correct answer is Choice (D).\r\n\r\nBecause the first equation has x with an understood coefficient of 1, you may want to use the substitution method to solve this system of equations. Use the first equation to solve for x in terms of y:\r\n\r\n\r\n\r\nNow substitute 22 – 2y in for x in the other equation, 7x – 3y = 1, and solve for y. (Make sure you use the other equation. Using the value of one variable in terms of another in the equation where you found it leads to a dead end.)\r\n\r\n\r\n\r\nYou can now put the numerical value of y in for y in either original equation and determine the value of x:\r\n\r\n\r\n\r\nBecause you know x is 4 and y is 9, you can determine which choice is not between x and y. The only choice that isn't between 4 and 9 is Choice (D).\r\n","item_vector":null},"titleHighlight":null,"descriptionHighlights":null,"headers":null,"categoryList":["academics-the-arts","teaching","skills-tests","praxis"],"title":"Practice Math Questions for Praxis: Solving Systems of Equations","slug":"practice-math-questions-praxis-solving-systems-equations","articleId":239019}]},"relatedArticlesStatus":"success"},"routeState":{"name":"Article4","path":"/article/academics-the-arts/teaching/skills-tests/praxis/practice-math-questions-praxis-solving-expressions-given-values-238995/","hash":"","query":{},"params":{"category1":"academics-the-arts","category2":"teaching","category3":"skills-tests","category4":"praxis","article":"practice-math-questions-praxis-solving-expressions-given-values-238995"},"fullPath":"/article/academics-the-arts/teaching/skills-tests/praxis/practice-math-questions-praxis-solving-expressions-given-values-238995/","meta":{"routeType":"article","breadcrumbInfo":{"suffix":"Articles","baseRoute":"/category/articles"},"prerenderWithAsyncData":true},"from":{"name":null,"path":"/","hash":"","query":{},"params":{},"fullPath":"/","meta":{}}},"dropsState":{"submitEmailResponse":false,"status":"initial"},"profileState":{"auth":{},"userOptions":{},"status":"success"}}

Practice Math Questions for Praxis: Solving Expressions with Given Values

By: Carla Kirkland and Chan Cleveland and

Updated: 05-01-2017

From The Book: Praxis Core: 1,001 Practice Questions For Dummies

Praxis Core: 1,001 Practice Questions For Dummies

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Some questions on the Praxis Core exam involve a simple plug-and-play approach, where you solve an expression by substituting given values for the variables. Sounds easy, right?

Well, yes and no: as you'll see in the following practice questions, you still need to watch out for double negatives and you have to know your order of operations.

Practice questions

What is the value of this expression if x = 1, y = –5, z = 8?
7x – 5y + 4z
A. –8 B. 103 C. 64 D. 36 E. –71
What is the value of this expression if k = –7, m = –10, and n = 11?

Answers and explanations

The correct answer is Choice (C).
Substitute each variable value in for its corresponding variable. Then simplify the result.
The correct answer is Choice (C).
You can substitute each variable value in for its corresponding variable and then simplify the resulting rational expression:

About This Article

This article is from the book:

Praxis Core: 1,001 Practice Questions For Dummies ,

About the book authors:

Carla Kirkland, founder and CEO of the Kirkland Group, an educational consulting firm, has helped educators prepare their students for standardized tests for more than 20 years.

Chan Cleveland, executive vice president of the Kirkland Group, is an English educator who has developed language arts resources for multiple school districts.

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Praxis ,

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