The inside angles of a triangle equal 180 degrees
so
(2x -2) + (x+6) + x = 180
combine like terms
4x + 4 = 180
subtract 4 from both sides
4x = 176
divide both sides by 4
x = 44
Now, wherever is says x, plug in 44
(x+6)
44 + 6
angle B is 50
2x - 2
2(44) -2
88-2
Angle A is 86
and the last angle is just 44
To check:
angle a + angle b + angle c =?= 180
86 + 50 + 44 =?= 180
180 = 180
Hope this helps