Let x = the smallest angle. The middle angle is 5 degrees more than 4 times the smallest angle, or 4x+5. The largest angle is 53 degrees more than the middle angle, or (4x+5)+53 = 4x + 58 All three angles must add up to 180°
x + 4x+5 + 4x+58 = 180°
9x + 63 = 180
9x = 117
x = 13°
The smallest angle = 13°
The middle angle = 4x+5 = 4(13)+5 = 57°
The largest angle = 57+53 = 110°