Answer:
P = 3
Q = -4
R = 22
Explanation:
Expand both sides and compare coefficients.
5Px^2 -PQx +10x -2Q = 15x^2 + Rx +8
Compare coefficients of x^2
5P = 15 => P = 3
Compare constant terms
-2Q = 8
Q = -4
Compare coefficients of x
-PQ + 10 = R
-(3)(-4) + 10 = R
R = 10 + 12 =22