SOLUTION: -15p is less than or equal to -90

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Question 24216: -15p is less than or equal to -90
Found 2 solutions by elima, kev82:
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
-15p%3C=-90
Divide both sides by -15;
-15p%2F-15%3C=-90%2F-15
p%3C=6
=)

Answer by kev82(151) About Me  (Show Source):
You can put this solution on YOUR website!
Hi,
Hopefully you've spotted elima's deliberate mistake :o. To see that their solution is wrong take p=0. Zero is not less than minus 90.
The golden rule to rember about inequalities is that when you multiply or divide an inequality by a negative number, you have to flip the inequality the other way round. To understand why, draw a few inequalities on a number line and then multiply by -1.
So let's give it a go, remebering the important rule.
-15p%3C=-90
%28%28-15%29%2F%28-15%29%29p%3E=%28-90%29%2F%28-15%29
p%3E=6
And there's your answer, don't forget to try a few numbers to check your answer.
Hope that helps
Kev