Question

The perimeter of a trapeziod is 39a - 7. Three sides have the following lengths: 9a, 5a + 1, and 17a - 6. What is the length of the fourth side?

Answer 1

6a - 2

Explanation:

Add all the sides, that are given to you, up

(9a) + (5a + 1) + (17a - 6)

(14a + 1) + (17a - 6)

31a -5

Then subtract it by 39a - 7

(39a - 7) - (31a - 5)

6a - 2