Atriangle is such that the largest angle is 12 times the smallest angle. the third angle is 20 less than the largest angle. find the measure of each angle.

Let x be the smallest angle
Then largest angle: 12x
3rd angle: 12x-20

You know all the angles of a triangle add up to 180°.

x+12x+12x-20=180
25x=180+20
25x/25=200/25
x=8

Smallest angle: 8°
Largest angle: 12(8) —> 96°
3rd angle: 12(8)-20 —> 76°

Hope I helped :)