(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
1
((a^5/6)^6=a^5=[(1/3)^2/5)]^5=(1/3)^2=1/9
2
(a^7/12)^12=a^7=[(3/4)^2/7]^7=(3/4)^2=9/16
3
(a^-1/3)^30=a^-10=[(1/2)^-2/5]^-10=(1/2)^4=1/16
4
(a^-1/4)^20=a^-5=[(3/10)^-2]^-5=(3/10)^2=9/100
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