Corresponding Angles in Parallel Lines — Practice Geometry Questions

By Allen Ma, Amber Kuang

When two parallel lines are intersected by a third line — a transversal corresponding pairs of angles are formed. You can use the properties of these angles to find missing angles.

Practice questions

Use the figures and the given information to solve for the missing angles in the following questions.

  1. image0.png

    as shown in the following figure.

    image1.png

    If

    image2.png

  2. image3.png

    as shown in the following figure.

    image4.png

    If

    image5.png

Answers and explanations

  1. 80 degrees

    When two parallel lines are cut by a transversal, corresponding angles are formed.

    image6.png

    are corresponding angles, so they’re congruent:

    image7.png

    The three angles of

    image8.png

    add up to 180 degrees, so

    image9.png

  2. 35 degrees

    image10.png

    are supplementary, which means they add up to 180 degrees:

    image11.png

    form a straight line, so they also add up to 180 degrees:

    image12.png