Answer:

Step-by-step explanation:
13. The given angles are <em>alternate interior angles</em>, so these angles are <em>congruent</em>. Make an equation in which they are equal to each other and solve for x:

14. The given angles are <em>same-side interior angles</em>, so they are <em>supplementary</em>. Make an equation in which the sum of the angles is equal to 180° and solve for x:

15. If you remove the horizontal line, the given angles are <em>corresponding angles</em>. These are <em>congruent</em>. However, make sure to add back the horizontal transversal line. Since this creates a 90°, add this to the given angle value:

Now set this value equal to the other angle and solve for x:

:Done