Answer:
a. x = 14 (see explanation)
b. the arrows along the lines
Explanation:
The relationship of these two expressions is Same Side, which means their sum is 180.
plugging in
108 + 4x + 16 = 180 | Given
124 + 4x = 180 | Add the numbers
4x = 56 | Subtract 124 from both sides
x = 14 | Divide both sides by 4