Question

Can someone tell me the answer to this?

Answer 1

Answer:

x = 3 . (the angle size is 21 + 18 = 39)

Step-by-step explanation:

7x + 18 + 51 + 90 = 180

18 + 51 + 90 = 159

159 + 7x = 180

-159           -159

7x = 21

/7     /7

x = 3