SOLUTION: Solve the Inequality -x/7 + 4 > 3x

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Question 237636: Solve the Inequality -x/7 + 4 > 3x
Found 2 solutions by College Student, checkley77:
Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
%28-x%2F7%29%2B4%3E3x
4%3E3x%2B%28x%2F7%29
...same as to say...
4%3E%283x%2F1%29%2B%28x%2F7%29
So, multiply the LCD on the right side of inequality (which is 7)
4%3E%287%2A3x%29%2F%287%2A1%29%2B%281%2Ax%29%2F%281%2A7%29
4%3E%2821x%2F7%29%2B%28x%2F7%29
Combine fractions since they now have the same denominator...
4%3E22x%2F7
Multiply by 7 on both sides to get rid of fraction...
4%2A7%3E22x
Divide 22 from both sides of inequality to find values of x...
28%2F22%3Ex
Can you reduce 28/22 to a simpler fraction? Yes.
I'll let you finish it since it's the last step. :)

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
-x/7 + 4 > 3x
-x/7-3x>-4
(-x-3x*7)/7>-4
(-x-21x)/7>-4
-22x>-28
x<-28/-22 [Note: the > sign changes from > to < when dividing by a negative value.
x<14/11 ans.
Proof:
Let x=13/11
-13/11*1/7+4>3*13/11
-13/77+4>39/11
-.1688+4>3.545
3.8312>3.545