Question

factorize x²-y²+4z²-4xz

Answer 1

x² - y² + 4 z² - 4 x z

==> x² + 4 z² - 4 x z - y²

==> x² + ( 2 z )² - 2.2 z.x - y²

[ Using :  a² + b² + 2 ab = ( a + b )² ]

==> ( x - 2 z )² - y²

[ Using : a² - b² = ( a + b )( a - b) ]

==> ( x - 2 z - y )( x - 2 z  + y )

The answer is : ( x - 2 z - y )( x - 2 z + y )

Hope it helps :-)

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