Question

factorise 9 minus y square plus 2xy minus x square​

Answer 1

Step-by-step explanation:

9-y^2+2xy-x^2

9= y^2-2xy+x^2

9= (x-y)^2

x-y=3

Answer 2

Answer:

$(3 + x - y)(3 - x + y) \:$

Step-by-step explanation:

$9 - {y}^{2} + 2xy - {x}^{2} \\ = 9 - ( {y}^{2} - 2xy + {x}^{2} ) \\ = 9 - { (x - y)^{2} } \\ = (3)^{2} - (x - y) ^{2} \\ = (3 + x - y)(3 - x + y)$