Question

In the accompanying diagram of a parallelogram

ABCD ,DC= 5x-18, BC=3x-6, AB=2x+12 find measure BC. Please help

Answer 1

BC = 39

Explanation:

Given:

DC = 5x - 18,

BC = 3x - 6,

AB = 2x + 12

Opposite sides of a parallelogram are equal.

Therefore:

AB = DC

2x + 12 = 5x - 18

Collect like terms

12 + 18 = 5x - 3x

30 = 2x

Divide both sides by 2

15 = x

x = 15

BC = 3x - 6

Plug in the value of x

BC = 3(15) - 6 = 45 - 6

BC = 39