The sum of the angles in any triangle is 180 degrees.
angle B could be x
then angle A would be (x+30)
and angle C would be (x+60)
So the equation would be:
x + (x+30) + (x+60)=180
start by subtracting 30 and 60 from both sides
so 3x=90
now, just divide to get x, which is the measure of angle B.
After you get B, add 30 degrees for the measure of angle A, and 60 for the measure of angle C.
They should add up to 180 degrees.
+5478 
