6 500
.....................................
(a-1)²/(a-3)*(a+2-a)(a+2+a)/4(a-1)(a+1)-3/a(a-1)=
=(a-1)²/(a-3)*4(a+1)/4(a-1)(a+1)- 3/(a²-a)=(a-1)/(a-3) -3/(a²-a)=
=(a³-a²-a²+a-3a+9)/(a-3)(a²-a)=(a³-2a²-2a+9)/(a-3)(a²-a)
a=-0,01
(-0,000001-0,0002+0,02+9)/[(-3,01)*(0,0001+0,01)=-9,019799/0,030401=
=-9019799/30401=-296 21103/30401
(х+5)²+(х-2)²+(х-7)(х+7)=11х+80
х²+10х+25+х²-4х+4+х²-49-11х-80=0
3х²-5х-100=0
D = 25+1200=1225=35²
х1=(5+35)/6=40/6= 6 целых (2/3)
х2=(5-35)/6=-(30/6)=-5
ответ: 6 целых (2/3)
-5
X-12/x-13=12/11
11x-132=12x-156
-x=24
x=24