Answer:
x + 6x+10 + x+2 = 180
x = 21
Explanation:
The sum of the angles of a triangle add to 180 degrees
x + 6x+10 + x+2 = 180
Combine like terms
8x + 12 = 180
Subtract 12 from each side
8x+12-12 = 180-12
8x =168
Divide each side by 8
8x/8 = 168/8
x =21