Answer:
x3
Step-by-step explanation:
4x^2+28x+44
f(x+3)=4x^2+4x-4
=4(x+3)^2+4(x+3)-4
=4(x^2+6x+9)+4x+12-4
=4x^2+24x+36+4x+12-4
=4x^2+28x+44