Question

I don’t know how to solve this

Answer 1

Answer: x = 80° and y = 85°

Step-by-step explanation: In a cyclic quadrilateral, opposite angles add up to 180°.

x + (x + 20) = 180 and

y + (y + 10) = 180.

Solving for x

x + (x + 20) = 180

x + x + 20 = 180

2x = 180 - 20

2x = 160

2x/2 = 160/2

x = 80°

Solving for y

y + (y + 10) = 180

y + y + 10 = 180

2y = 180 - 10

2y = 170

2y/2 = 170/2

y = 85°

Answer 2

18. x = 80°

19. y = 85°

Explanation:

Opposite angles of an inscribed quadrilateral are supplementary.

18.

x + x + 20 = 180

2x = 160

x = 80

Answer: x = 80°

y + y + 10 = 180

2y = 170

y = 85

Answer: y = 85°