Question

Find the value of x. Then find the measure of each labeled angle.

x= ____° (Simplify your answer.)
13x°= _____° (Simplify your answer.)
7x°= ____° (Simplify your answer.)

Answer 1

Answers are
x= 9
13x°= 117
7x°= 63

Step by step

Find the value of x.

the sum of the measures of the interior angles of a parallelogram is 360 degrees

13x + 13x + 7x + 7x = 360
Combine

40x = 360

Divide both sides by 40 to solve

x = 9


So from our original equation

13x + 13x + 7x + 7x = 360

13(9) + 13(9) + 7(9) + 7(9) = 360

117 + 117 + 63 + 63 = 360
Combine

360 = 360

Answer 2

13x + 7x = 180 (corresponding angles, sum of adjacent angles on a straight line=180)

20x = 180

x = 9

Substitute x into angle measures to find values.

13x° = 13(9)

= 117°

7x° = 7(9)

= 63°