Angle T and R are vertical angles meaning they are equal so combine the equations: 31x - 4 = 29x + 4, then solve using inverse operations
subtract 31x from both sides to get -4 = -2x + 4
Then subtract 4 from both sides to get -8 = -2x, now that we have isolated the variable we have to divide by -2 on both sides getting us x = 4, then plug in the four to the equation for angle R getting you 29 times 4 which equals 116 + 4 = 120
