Answer:
x = 5
Explanation:
the sum of the 3 angles in a triangle = 180°
sum the 3 angles, equate to 180 and solve for x
5x + 2 + 2x + 53 + 90 = 180 ( simplify left side )
7x + 145 = 180 ( subtract 145 from both sides )
7x = 35 ( divide both sides by 7 )
x = 5