Question

PTĐTTNT: 2xy + 16 - x² - y²

Answer 1

\(2xy+16-x^2-y^2\)

\(=16-\left(x^2-2xy+y^2\right)\)

\(=16-\left(x-y\right)^2\)

\(=\left(4-x+y\right)\left(4+x-y\right)\)

Answer 2

`2xy + 16 - x^2 - y^2 +16`

`= 16-(x^2 - 2.x.y +y^2) `

`= 4^2 - ( x-y)^2`

`= ( 4-x+y)(4+x-y)`