В
x²+4x-77=0
x1+x2=-4 U x1*x2=-77⇒x1=-11 U x2=7
x²+13x+22=0
x1+x2=-13 U x1*x2=22⇒x1=-11 U x2=-2
(x-7)(x+11)/4(x+1)*2(x+1)/(x+11)(x+2)=(x-7)/2(x+2)
г
x²-6x-72=0
x1+x2=6 U x1*x2=-72⇒x1=-6 U x2=12
x²+3x-18=0
x1+x2=-3 U x1*x2=-18⇒x1=-6 U x2=3
x/(x-12)(x+6)+3/(x+6)(x-3)=(x²-3x+3x-36)/(x+6)(x-12)(x-3)=
=(x-6)(x+6)/(x-12)(x+6)(x-3)=(x-6)/(x-12)(x-3)
X/2=1
x/2=1*2
x=2 ответ: х=2
3.6а-6.2-4(2.1а-0.3)= <span>3.6а-6.2-8.4а+1.2= -4.8а-5
Если а= -</span>
, по -4.8а-5= -4.8*0.25-5= -6.2