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Algebra
How to Add and Subtract Fractions in Algebra (Video)
In algebra, adding and subtracting fractions is easy when you find the common denominator. This video shows you how to convert fractions for the common denominator. After you determine the common denominator, you can add and subtract fractions, including story problems, with ease. [more…]
Calculus
How to Find the Volume of a Solid with a Circular Cross-Section (Video)
Calculus allows you to calculate the volume of conical objects by dividing the object into an infinite number of circular cross-sections - geometrical shapes resembling pancakes or washers - and adding up the volume of all those cross-sections through integration. This video tutorial shows you how. [more…]
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Geometry
Mastering the Formal Geometry Proof
Suppose you need to solve a crime mystery. You survey the crime scene, gather the facts, and write them down in your memo pad. To solve the crime, you take the known facts and, step by step, show who committed [more…]
Geometry
Sizing Up the Area of a Polygon
Not only can polygons be classified by the number of sides they have and by their angles, but they can also be grouped according to some of their qualities. Polygons can have three personality characteristics [more…]
Geometry
Simple and Easy Geometry Tips and Tools
The first rule of life? Life (as well as geometry) can be difficult. But why make it more difficult than it has to be? Do you need help with geometry? Here are 11 tried-and-true tips to make your forays [more…]
Geometry
Measuring and Making Angles
On a map, you trace your route and come to a fork in the road. Two diverging roads split from a common point and form an angle. The point at which the roads diverge is the [more…]
Geometry
Classifying Three Types of Triangles
Triangles are classified according to the length of their sides or the measure of their angles. These classifications come in threes, just like the sides and angles themselves. That is, a triangle has [more…]
SPSS For Dummies Cheat Sheet
SPSS is an application that performs statistical analysis on data. Entering and manipulating information in the application can be done by using SPSS’s proprietary language, which is known as the Syntax [more…]
How to Distribute Variables
Distributing variables over the terms in an algebraic expression involves multiplication rules and the rules for exponents. When different variables are multiplied together, you can write them side by [more…]
How to Add Positive Numbers with Negative Numbers
When the signs of two numbers that you're adding are different, forget the signs and find the difference between the numbers — which is the difference between their absolute values. The number farther [more…]
How to Subtract Positive and Negative Numbers
Subtracting positive and negative numbers is really easy to do: You don’t! Just change the minus sign (the one that's the operator) to a plus sign, change the number that the minus sign was in front of [more…]
How to Multiply and Divide Positive and Negative Numbers
Multiplying and dividing positive and negative numbers is a simple operation with two numbers. With three or more, it is also straightforward, but you use the Even-Odd Rule. [more…]
How Zero Affects Positive and Negative Numbers
It isn’t too tricky to perform operations using positive and negative numbers with zero. You follow normal addition and subtraction rules, and what zero does to the final sign depends on where the zero [more…]
How to Reorder Operations with the Commutative Property
The commutative property makes working with algebraic expressions easier. The commutative property changes the order of some numbers in an operation to make the work tidier or more convenient — all without [more…]
How to Apply the Associative Property
The associative property comes in handy when you work with algebraic expressions. Use the associative property to change the grouping in an algebraic expression to make the work tidier or more convenient [more…]
How Fractions Are Put Together
Fractions just have two parts: a numerator and a denominator. The denominator, or bottom number, indicates the total number of items. The numerator, or top number, tells you how many of the total [more…]
How Proper Fractions Work
The simplest type of fraction is a proper fraction, which is always just part of one whole thing. In a proper fraction, the numerator is always smaller than the denominator, and its value is always less [more…]
What to Do When Fractions Don't Reduce
It’s always nice when you can reduce a fraction to make it more user-friendly. The fraction 3/4 is much nicer than 447/596. Sometimes, though, the fraction just doesn’t want to cooperate. In these cases [more…]
How to Divide Fractions
Dividing fractions is as easy as pie! In fact, after you change mixed numbers to improper fractions, dividing fractions is just like multiplying fractions, except that you flip the numerator and the denominator [more…]
How to Convert Decimals to Fractions
Converting decimals into fractions isn't hard. To convert a decimal into a fraction, you put the numbers to the right of the decimal point in the numerator [more…]
How to Convert Fractions to Decimals
You can convert all fractions to decimals. The decimal forms of rational numbers either end or repeat a pattern. To convert fractions to decimals you just divide the top by the bottom — divide the numerator [more…]
Using Exponents to Simplify Equations
An exponent is a small, superscripted number written above and to the right of a larger number, the base — this tells you how many times you multiply the base by itself. This repeated multiplication is [more…]
How to Write Numbers in Scientific Notation
Scientific notation is a standard way of writing very large and very small numbers so that they're easier to both compare and use in computations. To write in scientific notation, follow the form [more…]
How to Multiply Exponents
You can multiply many exponential expressions together without having to change their form into the big or small numbers they represent. When multiplying exponents, the only requirement is that the bases [more…]
How to Divide Exponents
You can divide exponential expressions, leaving the answers as exponential expressions, as long as the bases are the same. To divide exponents (or powers) with the same base, subtract the exponents. Division [more…]
How to Check an Answer to an Algebra Problem
Checking your answers when doing algebra problems is always a good idea — after all, if there's a way to ensure that you have the correct answer, it's worth the time, isn't it? You check your answers in [more…]
How to Work with Coefficients
Algebra simplifies expressions with coefficients, which are numbers preceding variables. For example, 3 is the coefficient in 3x. Rather than using a multiplication sign between 3 and [more…]
How to Add and Subtract Variables
Whether you add or subtract variables, you follow the same rule, even though they have different operations: when adding or subtracting terms that have [more…]
How to Add and Subtract with Powers
To add or subtract with powers, both the variables and the exponents of the variables must be the same. You perform the required operations on the coefficients, leaving the variable and exponent as they [more…]
How to Multiply Variables
When variables are the same, multiplying them together compresses them into a single factor (variable). But you still can’t combine different variables. When multiplying variables, you multiply the coefficients [more…]
Dividing Variables in Algebra
Dividing variables in an algebra problem is fairly straightforward. Each variable is considered separately. The number coefficients are reduced the same as in simple fractions. When dividing variables, [more…]
