Answer:
50 deg
Step-by-step explanation:
In an right triangle, the acute angles are complementary. That means their measures have a sum of 90 deg.
m<C + m<B = 90
7x - 20 + 4x = 90
11x = 110
x = 10
m<ACB= 7x - 20
m<ACB = 7(10) - 20
m<ACB = 70 - 20
m<ACB = 50
Answer: m<ACB = 50 deg
