Answer:
159°
Explanation:
A circle measures 360°. We can use this knowledge to find the unknown angles.
(10x + 9) + (6x - 13) + 34 + 90 = 360
Combine like terms and solve for x.
16x + 120 = 360
16x = 240
x = 15
So, we have found the value of x, and can now find m∠YZU.
10(15) + 9 = m∠YZU
m∠YZU = 159°
We can ascertain that this is the answer by plugging in x for the initial equation we created.
(10(15) + 9) + (6(15) - 13) + 34 + 90 = 360
159 + 77 + 34 + 90 = 360 It works!