Question

( 5x - 3y ) ( x - 7y ) - ( x + 3y ) ( 3x - 4y )

Answer 1

Hey buddy !!

5x ( x - 7y ) - 3y ( x - 7y ) - x ( 3x - 4y ) 3y ( 3x - 4y ) = 0

5x^2 - 35xy- 3xy + 21y^2 - 3x ^2 +4xy +9xy - 12y^2 = 0

Answer 2

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$= > (5x - 3y)(x - 7y) - (x + 3y)(3x - 4y) \\ \\ = (5 {x}^{2} - 3xy - 35xy + 21 {y}^{2} ) - (3 {x}^{2} + 9xy - 4xy - 12 {y}^{2} ) \\ \\ = 5 {x}^{2} - 38xy + 21 {y}^{2} - 3 {x}^{2} - 5xy + 12 {y}^{2} \\ \\ = 2 {x}^{2} - 43xy + 33 { y }^{2}$
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