SOLUTION: Just not getting this, please help??? Find the product: (4x-5y)(4x+5y)

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Question 382975: Just not getting this, please help???
Find the product: (4x-5y)(4x+5y)
Found 2 solutions by CharlesG2, edjones:
Answer by CharlesG2(834) About Me  (Show Source):
You can put this solution on YOUR website!
Just not getting this, please help???
Find the product: (4x-5y)(4x+5y)

these are 2 binomials (polynomials with 2 terms)
use FOIL (First Outer Inner Last)
(4x - 5y)(4x + 5y)
16x^2 + 4*5*x*y - 4*5*x*y - 25y^2
16x^2 - 25y^2, this is also a difference of squares

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
(4x-5y)(4x+5y)
Do FOIL to understand this.
F 16x^2
O 20xy
I -20xy
L -25y^2
.
=16x^2-25y^2
.
Ed