Question

Are the signs right?

4y^2-9z^2
(2y-9z)(2y-9z)
F= 4y^2
O=-6yz
I= -6zy
L= 9z^2
=4y^2- 9z^2

Answer 1

I am thinking maybe +- or ++ not - -

Answer 2

(2y-9z)(2y-9z)
F = 4y^2
O = -18yz
I = -18yz
L = 81z^2

Hence (2y-9z)(2y-9z) =4y^2-36yz+81z^2

Answer 3

lol, I meant 3z not 9z.

Answer 4

In that case...
(2y-3z)(2y-3z)
F = 4y^2
O = -6yz
I = -6yz
L = 9z^2

Hence (2y-3z)(2y-3z) =4y^2-12yz+9z^2

Answer 5

it must be + + because +- wouldnt work. I dont think.