Answer:
x = 3
Explanation:
Pre-Solving
We are given triangle RTS. We can see that the points R and S are on the line QS.
We know that m<T = 25x, m<S = 57 + x and m<TRQ = 45x
We want to find the value of x.
Recall the exterior angle theorem: the measure of an exterior angle is equal to the sum of the two remote interior angles.
We can see that <TQR is an exterior angle - that is, it is outside of triangle RTS.
Solving
This means m<T + m<S = m<TQR
So:
25x + 57 + x = 45x
26x + 57 = 45x
Subtract 26x from both sides.
57 = 19x
Divide both sides by 19.
3 = x