Question

factorise 100x^2-16x^2-25y^2+40xy​

Answer 1

$100 {x}^{2} - 16 {x}^{2} - 25 {y}^{2} + 40xy \\ 100 {x}^{2} - (4.4 {x}^{2} - 2.4x.5y + 5.5 {y}^{2} ) \\ 100 {x}^{2} - {(4x - 5y)}^{2} \\ {(10x)}^{2} - {(4x - 5y)}^{2} \\ (10x + 4x - 5y)(10x - 4x + 5y) \\ (14x - 5y)(6x + 5y)$

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