Solve for X the mini box in the corner is 90 degree angle

X = 12

A triangle has a sum of interior angles equaling 180 degrees. Since the triangle has a right angle, 90 degrees, subtract 90 from 180.

There are 90 degrees left in the triangle. An angle of 35 degrees is given. 90 - 35 = 55. Thus, the final angle must equal 55 degrees.

Solve for x
3x + 19 = 55
- Subtract 19 from each side
3x = 36
- Divide by 3 to isolate x
x = 12

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