Question

B)Add −2x2+5xy+4y2, x2−2xy+y2

and 3x2+4xy−y2​

Answer 1

Answer:

The answer is 2+7xy+4y2+x2

Step-by-step explanation:

-4+5xy+4y2+x2-2xy+y2+6+4xy-y2

= -4+6+5xy-2xy+4xy+4y2+y2-y2+x2

= 2+3xy+4xy+5y2-y2+x2

= 2+7xy+4y2+x2

hence the answer is 2+7xy+4y2+x2

Answer 2

$\rm{\left(-2x^2+5xy+4y^2\right)+\left(x^2-2xy+y^2\right)+\left(3x^2+4xy-y^2\right)}$

$\rm{=-2x^2+5xy+4y^2+x^2-2xy+y^2+3x^2+4xy-y^2}$

$\rm{=-2x^2+x^2+3x^2+5xy-2xy+4xy+4y^2+y^2-y^2}$

$\rm{=2x^2+5xy-2xy+4xy+4y^2+y^2-y^2}$

$\rm{=2x^2+7xy+4y^2+y^2-y^2=2x^2+7xy+4y^2}$