I ran across this concept in the Math Forum and thought it interesting.
Positive and negative numbers
One thing that can help is to realize that mathematics is a world of its own that can be used to MODEL things in the real world, but, like any model, is not IDENTICAL to that real world. Negative numbers are part of the "model world", not the real world. So there are some situations...
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Let's look at a simple problem using the same principle. Suppose you made $10 an hour and worked 1/2 an hour. How much did you make? The answer is easy; it's $5. You found the answer by multiplying 10 x 1/2. Using the same principle multiply 360 x 1/18 and you...

Dayana,
Try by expanding the right side of the inequality (multiplying the 5 times the x and the 2). Next get all the "x" terms on one side of the inequality sign and the "numbers" on the other. Be careful when you do this because there is something in your math...

Casandra,
As withe answer to any question, you should ask "does the answer make sense?". For example, if you are traveling at 60 miles per hour for 60 minutes, you didn't travel 3600 miles (that doesn't make sense). You did travel 60 miles, because you changed the 60 minutes...