Answer:
f(x) = 3x^2 - 4x + 12
Explanation:
First, let's label the expression and do a little housekeeping:
X(2x+3)+(x-3)(x-4) should be f(x) = x(2x+3)+(x-3)(x-4).
If we perform the indicated multiplication, we get:
f(x) = 2x^2 + 3x + (x^2 - 7x + 12), or
f(x) = 2x^2 + 3x + x^2 - 7x + 12. Combine like terms to obtain:
f(x) = 3x^2 - 4x + 12