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selinaaa
Oct 14, 2008, 02:28 PM
how do you solve inequalities with fractions? Such as 2/5 x -5>3?
I realllllllllllllly need help!

ebaines
Oct 15, 2008, 02:37 PM
You can add and subtract numbers to both sides, just like with standard equations. You can also multiply (or divide) both sides by a factor, however, if the factor is negative then the inequality gets flipped. Consider a problem that is similar to yours:

4/7 x - 9 >3

Add 9 to both sides:

4/7 x > 12

Now multiply through by 7/4:

x > 12*7/4, or
x> 21.

Alternatively, you could start by multipying through by 7:

4/7x - 9 > 3
4x - 63 >21
Add 63 to both sides:
4x > 21+63
4x>84
Now divide through by 4:
x > 84/4, or
x>21.

You should be able to use this same process on your homework problem. Post back and let us know what you get or an answer.