Verified answer

1.)

[tex] - 3(y - x {)}^{2} + 7x(x - y) \\ - 3( {y}^{2} - 2xy + {x}^{2} ) + 7 {x}^{2} - 7xy \\ - 3 {y}^{2} + 6xy - 3 {x}^{2} + 7 {x}^{2} - 7xy \\ 4 {x}^{2} + xy - 3 {y}^{2} [/tex]

a) 4x²+xy-3y² [✓]

2.)

[tex]16x {y}^{2} - 4x {a}^{2} \\ 4x(4 {y}^{2} - {a}^{2} ) \\ 4x(2y - a)(2y + a)[/tex]

a) 4x(2y-a)(2y+a) [✓]

#ТокийскиеИтачи

#хорошаяучёба

А)

А)

Объяснение:

[tex] - 3(y - x) {}^{2} + 7x(x - y) =-3\left(y^{2}-2yx+x^{2}\right)+7x\left(x-y\right) =-3y^{2}+6yx-3x^{2}+7x\left(x-y\right) =-3y^{2}+6yx-3x^{2}+7x^{2}-7yx =-3y^{2}+6yx+4x^{2}-7yx =4x^{2}-xy-3y^{2} [/tex]

[tex]16xy {}^{2} - 4xa {}^{2} =4\left(4xy^{2}-xa^{2}\right) =x\left(4y^{2}-a^{2}\right) =\left(2y-a\right)\left(2y+a\right) =4x\left(2y-a\right)\left(2y+a\right) [/tex]