a = smallest angle
3a = largest angle
a + 30 = other angle
Angles in a triangle add up to 180 degrees.
a + 3a + a + 30 = 180 ---> Simplify the left side of the equation
5a + 30 = 180 ---> Subtract 30 from both sides
5a = 180 ---> Divide both sides by 5
a = 36
We want to find the largest angle, which is equal to 3a.
3a = 3 x 36
3 x 36 = 108
The largest angle is 108 degrees.