Help and plz add steps WORTH 50 POINTS

$450

step-by-step explanation:

first, you have to multiply 150x2=300

next, you have to add 150+300= 450

8(-10x+3.5y-7)

8×-10x + 8×3.5y + 8×-7

-80x + 28y - 56

therefore

-80x+28y-56 is the correct answer

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value