Answer:
[tex]\boxed {\boxed {\sf A. \ 18}}[/tex]
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.
[tex]56+(x+16)=90[/tex]
Combine the like terms on the right side. The 2 constants: 56 and 16 can be added.
[tex](56+16)+x=90\\[/tex]
[tex]72+x=90[/tex]
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.
[tex]72-72+x=90-72[/tex]
[tex]x=18[/tex]
x is equal to 18 and choice A is correct.
