Question

Solve for x below in the equation​

Answer 1

x = 10

Explanation:

See image. Due to the logic of vertically opposite angles (when one angle is equal to the other that is "vertically opposite" to it), the two angles that I have marked in the diagram are going to equal.

Therefore, if we were to write it out:

2x + 7x = 90

(vertically opposite angles)

9x = 90

∴ x = 10

Answer 2

Explanation:

7x + 2x =90 (being perpendicular)

9x =90

x =90/9

x =10

substiute the value of x

7x

=7*10

=70

2x

=2*10

=20