Question

The lines a and b intersect at point D.

What is the value of z?

Answer 1

5z+8=4z+20

5z-4z=20-8

z=12

Answer 2

The value of the z is 12 .

Explanation:

Definition of vertically opposite angle .

Vertically opposite angles is defines angles opposite to each other when two lines cross eachother .

Thus

(5z + 8)° = (4z + 20)°

(5z + 8) = (4z + 20)

Open the bracket

5z + 8 = 4z + 20

5z - 4z = 20 -8

z = 12

Therefore the value of the z is 12 .