Question

simplify both question with attachment​

Answer 1

1) (x+2y) (-3x-y) - (x+y) (x-y) + (x-2y) (-2x+y)

= x(-3x-y) +2y(-3x-y) - (x² - y²) + x(-2x+y) -2y(-2x+y)    [Using (a+b)(a-b)=a² - b²]  

= -3x² -xy -6xy - 2y² -x² + y² -2x² + xy + 4xy - 2y²

= -6x² -3y² -2xy

2) (a² + b²) (a² + b²) - (a² - b²) ( a² - b²)

= (a² + b²)² - (a² - b²)²

You can use whatever method u want, but here I'm using

(a + b)² = a² + b² + 2ab

= [apower 4 + bpower 4 + 2a²b2] - [apower 4 + bpower 4 - 2a²b²]

= apower 4 + b power 4 + 2a²b² - apower 4 - bpower4 + 2a²b²

= 4a²b²

Have a good day :3

Answer 2

Step-by-step explanation:

$1.$

$(x + 2y)( - 3x - y) - (x + y)(x - y) + (x - 2y)( - 2x + y)$

$( - 3x {}^{2} - xy - 6xy - 2y {}^{2}) - (x {}^{2} - y {}^{2} ) + ( - 2x {}^{2} + xy + 4xy - 2y {}^{2} )$

$- 3x {}^{2} - xy - 6xy - 2y {}^{2} - x {}^{2} + y {}^{2} - 2x {}^{2} + xy + 4xy - 2y {}^{2}$

$- 4x {}^{2} - 2xy - 5y {}^{2}$

$2.$

$(a {}^{2} + b {}^{2} )(a {}^{2} + b {}^{2} ) - (a {}^{2} - b {}^{2} )(a {}^{2} - b {)}^{2}$

$(a {}^{2} + b {}^{2} ) {}^{2} - (a { }^{2} - b {}^{2} ) {}^{2}$

$(a {}^{2} + b {}^{2} + a {}^{2} - b {}^{2} )(a {}^{2} + b {}^{2} - a {}^{2} + b {}^{2} )$

$(2a {}^{2})(2b {}^{2} )$

$4a {}^{2} b {}^{2}$

Hope this helps u Please make me as a brainliest