x = smallest angle, y = middle angle, z = largest angle
x + y + z = 180...interior angles of a triangle add up to 180 degrees
y = 1/2z.....z = 2y
y = 3x.......1/3y = x
1/3y + y + 2y = 180....multiply everything by 3
y + 3y + 6y = 540
10y = 540
y = 540/10
y = 54 <== the middle angle
z = 2y
z = 2(54)
z = 108 <=== largest angle
1/3y = x
1/3(54) = x
54/3 = x
18 = x <=== smallest angle
