SOLUTION: I'm solving inequalities and the question is 16x<=32or-5x<=-40 And I jsut want to know when solving each do you change -5 to positive five when you divide it with 40 or does

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Question 1046026: I'm solving inequalities and the question is
16x<=32or-5x<=-40
And I jsut want to know when solving each do you change -5 to positive five when you divide it with 40 or does it stay as -5?
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
16x%3C=32, coefficient on x is positive. Multiplying both sides by 1%2F16 makes no change regarding order.

16x%281%2F16%29%3C=32%281%2F16%29
x%3C=2



-5x%3C=-40
Where is -40 on a real number line? Some fourty units to the left of 0.
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Where is -5x on a real number line according to your given inequality? Some number of units, variable, to the LEFT of the -40; so the order of the two members are now clear. Make a number line and label all the parts and this helps to see all this.
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Multiplicative inverse of -5 is -1%2F5.
Now, refer again to the number line if this will help.
What happens to order when multiplying -5x%28-1%2F5%29 and the -40%28-1%2F5%29?

The order of the resulting members is reversed.
-5x%28-1%2F5%29%3E=-40%28-1%2F5%29
x%3E=8