5:
\(=4x^2-12x-x^2+10x-25-3\left(x^2+2x+1\right)+\left(2x+2\right)^2-4x^2+5\)
\(=-2x-20-x^2-3x^2-6x-3+4x^2+8x+4\)
=-20-3+4
=-23+4=-27
6:
\(=\left(2x-3\right)\left(x^2-4\right)-2\left(x^3+9x^2+27x+27\right)-x^3+12x^2-48x+64+x^3-27+9x^2+110x\)
\(=2x^3-8x-3x^2+12-2x^3-18x^2-54x-54+21x^2+62x+37\)
=12+37
=49
