how do i factor 4x^2+9xy-9y^2

Question

anonymous · Answer

i found that the factored version of 4x^2+9xy-9y^2 is (x+3y)(4x-3y)

anonymous · Answer

thanks how did you find the answer?

anonymous · Answer

Suppose you have the problem:
x2 +6x+9
you try to find two numbers that add to be 6 and multiply to be 9. in this case it's 3 and 3. so you exchange the 6x for 3x +3x . . .
x2 +3x +3x +9 then you group the first two and the second two terms . . .
(x2+3x)+ (3x+9)
next you take out the biggest number they have in common.and leave whats left in the ( )
x(x+3)+ 3(x+3)
now the answer is the stuff inside the ( ) times the stuff outside
(x+3)(x+3)
(by the way, sorry or the delay, i had to brb)
hope this helps