Question 215617
4x +7<5x-2<8x,,,,add  2  to  each  term
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4x +7 +2 < 5x-2+2 < 8x +2
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4x +9<5x<8x+2,,,,,divide  by  5
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(4x+9)/5 < 1x < (8x+2)/5,,,,,
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or,,,,.8x +1.8<1x<1.6x +.4,,,,
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solving  using  two  problems,,,.8x +1.8<1x,,,subtract  .8x
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1.8<.2x,,,,divide  by  .2
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9<1x,,,,,answer
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or  1x<1.6x +.4,,,,,subtract 1.6x
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-.6x < .4,,,,,,,divide  by  (-.6)  and  flip  sign
.,,,,1x>-.667,,,,,,,answer
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check,,,,,,,a,,,,-.667,,,,,b,,,,9,,,,,c
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a,  Let  x= -1,,,,,,4(-1)+7<5(-1)-2<8(-1)
,,,,,,,,,-4 +7 <-5<-8
,,,,,,,,3 <-5<-8,,,,,,not  true
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b,,,,let  x= 0,,,,,7<-2<0,,,,,not  true
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c,,,,,let x =10,,,,4(10)+7<5(10)-2<8(10)
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,,,,,,,,,,,,,,47<48<80,,,,,,,ok
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Therefore  answer  is  1x >9
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