Answer:
-10x +34
Step-by-step explanation:
$(x-4)(x-7)$
(x-4)(x-7) &= x(x-7) - 4(x-7)\\
&=x^2 - 7x -4x +28\\
&=x^2 - 11x + 28.
$(3-x)(2+x)$
(3-x)(2+x) &= 3(2+x) - x(2+x)\\
&=6 + 3x - 2x - x^2\\
&= 6+x -x^2.
(x-4)(x-7) + (3-x)(2+x) &= (x^2 - 11x + 28) + (6+x-x^2)\\
&= (x^2 - x^2) + (-11x + x) + (28 + 6)\\
=-10x + 34
