Angles in triangle add up to 180°, thus to solve for the value of x, we add up our angles and equate it to 180. 80+(2x+2)+(5x)=180 simplifying this we have: 80+2x+2+5x=180 80+2+5x+2x=180 82+7x=180 7x=180-82 7x=98 x=98/7 x=14 thus the value of x is: 14°
