Answer:
x = 108
Step-by-step explanation:
added together, these angles equal 360.
x - 1 + x - 71 + 216 = 360
combine like terms
2x - 72 + 216 = 360
2x + 144 = 360
subtract 144 from both sides of the equation
2x + 144 -144 = 360 - 144
2x = 360 - 144
2x = 216
x = 216/2
x = 108
