42х=1008
х=1008:42
х=24
ответ: 24
3a+b=12, b=12-3a, a=(12-b)/3
c+8d=15, c=15-8d, d=(15-c)/8
18m-n=3, n=18m-3, m=(3+n)/18
-p-9q=4, -p=4+9q, p=-4-9q, -9q=4+p, q=(-4-p)/9
9х²-24х+16-(10х<span>²+40х+4х+16</span>)=0
9х<span>²-24х+16-10х</span><span>²-40х-4х-16</span>=0
-х<span>²-68х=0
х(-х-68)=0
х=0 -х-68=0
-х=68
х=-68
Ответ:х=0;х=-68
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