Question

у2+10у+25-х2=?

4z2+4uz+u2-16=?

81-9x2-6xy-y2=?
Помогите, очень при очень срочно

Answer 1

$y^2+10Y+25-x^2=0 \\ y^2+10y+5^2=x^2 \\ (y+5)^2=x^2 \\ y+5=x$

$4z^2+4uz+u^2-16=0 \\ (2z+u)^2=16 \\ 2z+u=4$

$81-9x^2-6xy-y^2=0 \\ 9x^2+6xy+y^2=81 \\ (3x+y)^2=81 \\ 3x+y=9$

Answer 2

у2+10у+25-х2= (y+5)² -x² =(y+5-x)(y+5+x);4z2+4uz+u2-16=(2z+u)²-4² =(2z+u-4)(2z+u +4);
81-9x2-6xy-y2= 9² -(3x+y)² =(3-3x-y)(3+3x+y).