SOLUTION: Help understanding negative numbers like -x² when x= -2

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Question 459838: Help understanding negative numbers like -x² when x= -2
Answer by math-vortex(648) About Me  (Show Source):
You can put this solution on YOUR website!
You want to evaluate the expression -x%5E2 for x = -2.
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There are a lot of negatives running around here, but don't worry. It's pretty straight forward.
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We begin by substituting -2 for x in the expression.
-x%5E2=-%28-2%29%5E2
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At this point, we have to decide how to deal with the two negative signs. Do we say "two negatives make a positive" and square positive 2, OR do we square negative 2 and then add the other negative sign. We will get different answers depending on what we choose.
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This is why mathematicians decided on an Order of Operations. (It's a good thing to always get the same answer for the same problem.)
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In your problem, the order of operations is to square the -2, then add the other negative sign, because exponents come before multiplication/division. or addition/subtraction.
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%28-2%29%5E2=4
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Then we add on the other negative sign in front, so our answer is -4.
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-%28-2%29%5E2=-4
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I hope this helps.
Send me a message if you still have questions about this.
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Ms.Figgy
math-vortex