Question

Quadrilateral BCDE is a rhombus. What is DE?
D
с
9z
E
2+72
B

Answer 1

DE = 81

Explanation:

The sides of a rhombus are congruent , thus

9z = z + 72 ( subtract z from both sides )

8z = 72 ( divide both sides by 8 )

z = 9

Then

BC = 9z = 9 × 9 = 81

Since the sides are congruent, then DE = 81