Answer: x = 17
Step-by-step explanation: Since ray SQ bisects <TSR, we know
that the m<TSQ ≅ m<QSR by the definition of an angle bisector.
So we can setup the equation (3x - 9) + (3x - 9) = 84
using the angle addition postulate.
Simplifying on the left gives us 6x - 18 = 84.
Now add 18 to both sides to get 6x = 102.
Now divide both sides by 6 so x = 17.
