The answer is If you would like to find the expression that is equivalent to (t*s)(x), you can calculate this using the following steps:
s(x) = x - 7
t(x) = 4x^2 - x + 3
(t*s)(x) = t(s(x)) = t(x - 7) = 4(x - 7)^2 - (x - 7) + 3 = 4(x - 7)^2 - x + 7 + 3
The correct result would be 4(x – 7)2 – (x – 7) + 3.