Question

(x+y)(-3x-y)-(x+y)(x-y)+(x-3y)(-3x+y)
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Answer 1

Answer:

-7x^2+6xy-3y^2

Step-by-step explanation:

= (x+y)(-3x-y)-(x+y)(x-y)+(x-3y)(-3x+y)

= (-3x^2-xy-3xy-y^2)-(x^2-xy+xy-y^2)+ (-3x^2+xy+9xy-3y^2)

= (-3x^2-4xy-y^2)-(x^2-y^2)+(-3x^2+10xy-3y^2)

= -3x^2-4xy-y^2-x^2+y^2-3x^2+10xy-3y^2

= -7x^2+6xy-3y^2