Pliss ta teraz. Matematyka z kluczem klasa 8 zadanie 2 strona 79

[tex]a)\\\\x^2-(x+2)(x-1)=x^2-(x^2-x+2x-2)=x^2- x^2+x-2x+2=-x+2\\\\x=-0,5\\\\-x+2=-(-0,5)+2=0,5+2=2,5\\\\b)\\\\(x+2)(6(x+4)-5(x+6))=(x+2)(6x+24-5x-30)=(x+2)( x-6)=\\\\=x^2-6x+2x-12=x^2-4x-12\\\\x=-0,5\\\\x^2-4x-12=(-0,5)^2-4*(-0,5)-12=0,25 +2-12=-9,75[/tex]