The 3 inside angles of a triangle need to equal 180
Now we can add all 3 angles and solve for x:
2x +x +60 = 180
Add 2x and x to get 3x
We now have 3x +60 = 180
Subtract 60 from each side:
3x = 120
Divide both sides by 3 to get x
x = 120/3
x = 40
Since angle b = x, angle b = 40 degrees
Angle a = 2x , so angle a = 2 *40 = 80 degrees
