Answer:
x = 20
Step-by-step explanation:
x + 2x + (x + 10) = 90° (right angle)
x + 2x + x + 10 = 90
Add like terms
4x + 10 = 90
4x = 90 - 10 (substraction property of equality)
4x = 80
x = 80/4 (division property of equality)
