Question 259965
If f(s) = 9 and p(q) = 2f(s) = 2(9) = 18
so, subtituting to p(q) = q^2 - 7
                   18 = q^2 - 7
                   18 + 7 = q^2
                   q^2 = 25
taking the sq. root
                   q = +5 and -5 - -- ans