Question

jus completed my homework. so if anyone wants to check it. I would appreciate it.
(y^2-8)(5y^2-8y+7)= 5y^4-8y^3-33y^2+64y-56?

Answer 1

5y^4 - 8y^3 + 7y^2 - 40y^2 - 64y - 56

You forgot the term y^2 * +7

Answer 2

Then you add like terms.

5y^4 - 8y^3 - 33y^2 - 64y - 56

OOPS You are correct.

Answer 3

There is a conflict in the sign of the 64y, I haven't verified what sign it is

Answer 4

64y should be positive... my bad

Answer 5

agree

Answer 6

let me try it again, i'm pretty sure it's -

Answer 7

No need India, you've got it right, but review never hurts