Question

Помогите пожалуйста решить!СРОЧНО! ​

Answer 1

1.

$\frac{17^2-16^2}{33}+17\cdot 16=\frac{(17-16)(17+16)}{33} +17\cdot 16= \frac{1\cdot 33}{33}+272=1+273=273$

2.

a)

$3b^3-24=3(b^3-8)=3(b^3-2^3)=3(b-2)(b^2+2b+b^2)$

b)

$a^2-8ay+16y^2+3a-12y = (a-4y)^2+3(a-4y)=(a-4y)(a-4y+3)$

3.

$(2y-5)^2+(3y-5)(3y+5)+40y=4y^2-20y+25+9y^2-25+40y=13y^2+20y=y(13y+20)$

при

$y=-2\\-2\cdot (13\cdot (-2)+20)=-2\cdot (-26+20)=-2\cdot (-6)=12$

4.

$\left \{ {{x^2-y^2=64} \atop {x-y=2}} \right. \\\left \{ {{x=2+y} \atop {(2+y)^2-y^2=64}} \right. \\\left \{ {{x=2+y} \atop {(4+4y+y^2-y^2=64}} \right. \\\left \{ {{x=2+y} \atop {4y=60}} \right. \\\left \{ {{y=15} \atop {x=2+15=17} \right.$