х- лет девочке
х+4+26=3*(х+4)
х=9
9 лет девочке
35 папику
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0,01ab × 100a = a²b
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1) х не равно 5
2) в не равно -2
3) х не равно -2
1. <span>5-0.2у=0.3у-3.9
5+3.9=0,3у+0,2у
0,5у=8,9
у= 17,8
</span><span>2) 1-1.7х-(0.8х+ 2)=3.4
</span> 1-1,7х-0,8х-2=3,4
-2,5х=3,4+2-1
-2,5х=4,4
х=- 1,76
Y=(x+2)^2+1
y=x^2+4x+4+1
y=x^2+4x+5