Answer:
Step-by-step explanation:
The two angles are inside a right angle. The small box signifies a right angle/ 90° angle.
Therefore, the sum of the angle measures must equal 90. We can set up an equation.
Combine the like terms on the right side. The 2 constants: 56 and 16 can be added.
Since we are solving for x, we must isolate the variable. 72 and x are being added. The inverse of addition is subtraction, so subtract 72 from both sides.
x is equal to 18 and choice A is correct.