8(-10x+3.5y-7)
8×-10x + 8×3.5y + 8×-7
-80x + 28y - 56
therefore
-80x+28y-56 is the correct answer
77
step-by-step explanation:
answer is the third choice:
3x^5+4x^4+x^3+2x^2-10x-7=0