Answer: 21
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Work Shown:
Vertical angles are always congruent.
This means they are equal in measure.
A = B
3x-30 = 2x-9
3x-2x = -9+30
x = 21
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Side note:
if x = 21, then,
A = 3*x-30 = 3*21-30 = 33 degrees
B = 2*x-9 = 2*21-9 = 33 degrees
