Answer:
x = 29, C
Explanation: We are given that total angle is 90°, or a right angle. This means that the two complementary angles must equal 90° together.
Create the equation:
2x - 4 + x + 7 = 90
Solve algebraically:
3x + 3 = 90
3x + 3 - 3 = 90 - 3
3x = 87
3x / 3 = 87 / 3
x = 29 or C
