Answer:
[tex]6x^3+40x^2-62x+16[/tex]
Step-by-step explanation:
[tex]6xx^2+6x\cdot \:7x+6x\left(-8\right)-2x^2-2\cdot \:7x-2\left(-8\right)\\=6x^3+42x^2-48x-2x^2-14x-16\\6x^3+40x^2-62x+16[/tex]
