Question 202387: -118<-7a+1<1
Answer by RAY100(1637)   (Show Source):
You can put this solution on YOUR website! -118<-7a+1<1
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subst 1
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-119<-7a<0
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divide by -7,,,flip inequality signs
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17>a>0
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check
a>17,,test point a=20,,,-7(20)+1=-139,,,-118<-139<1,,,,,no
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a<0,,,test point a=-1,,-7(-1)+1= 8,,,,-118<8<1,,,,,no
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17>a>0,,,test point,a=10,,-7(10)+1=-69,,,-118<-69<1,,,ok
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therefore confirmed,,17>a>0
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