Answer is choice C) x = 37
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Work Shown:
Add up the angles and set it equal to 180. Solve for x
(2x-9) + (2x+4) + (x) = 180
2x-9+2x+4+x = 180
(2x+2x+x)+(-9+4) = 180
5x-5 = 180
5x-5+5 = 180+5
5x = 185
5x/5 = 185/5
x = 37