Question

помогите пожалуйста Алгебра 8 класс

Answer 1

Ответ:

$1) 2+3=5\\\\ 2)-4+1=-3\\\\ 3)-2+6=4\\\\ 4)-5+(-1)=-6$

$\displaystyle 1)x^2-5x+6=0\\x^2-2x-3x+6=0\\x(x-2)-3(x-2)=0\\(x-2)(x-3)=0\\x-2=0,x-3=0\\x_{1}=2,x_{2}=3\\\\ 2)x^2+3x-4=0\\x^2+4x-x-4=0\\x(x+4)-(x+4)=0\\(x+4)(x-1)=0\\x+4=0,x-1=0\\x_{1}=-4,x_{2}=1\\\\ 3)x^2-4x-12=0\\x^2+2x-6x-12=0\\x(x+2)-6(x+2)=0\\(x+2)(x-6)=0\\x+2=0,x-6=0\\x_{1}=-2,x_{2}=6\\\\ 4) x^2+6x+5=0\\x^2+5x+x+5=0\\x(x+5)+x+5=0\\(x+5)(x+1)=0\\x+5=0,x+1=0\\x_{1}=-5,x_{2}=-1$