Answer:
x = 56
Explanation:
The sum of a triangle add up to 180, so add all of the angles in the triangle and equate to 180
x + x + 7 + x + 5 = 180
collect like terms to simplify
3x + 12 = 180
subtract 12 on both sides
3x = 180 - 12
3x = 168
divide 3 on both sides
x = 168 ÷ 3
x = 56