SOLUTION: -x/3=3 SOLVE Ive tried multiplying both sides by 3 and then multiplying the top number by 3 and solving and its still not working.. PLEASE let me know what im doing wrong

Algebra ->  Testmodule -> SOLUTION: -x/3=3 SOLVE Ive tried multiplying both sides by 3 and then multiplying the top number by 3 and solving and its still not working.. PLEASE let me know what im doing wrong      Log On


   

Question 124206: -x/3=3 SOLVE
Ive tried multiplying both sides by 3 and then multiplying the top number by 3 and solving and its still not working.. PLEASE let me know what im doing wrong
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given:
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%28-x%29%2F3=3+
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When you multiply both sides by 3 you get:
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%283%2A%28-x%29%29%2F3+=+3%2A3
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On the left side the 3 in the numerator cancels with the 3 in the denominator to give:
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%28cross%283%29%2A%28-x%29%29%2Fcross%283%29+=+3%2A3
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On the left side you are left with just -x and on the right side the 3 times the 3 is 9.
This makes the equation:
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-x+=+9
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But you want to solve for +x, so just multiply both sides by -1 and you have:
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x+=+-9
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Check the answer by returning to the original equation you were given and substitute into
that equation -9 for x. So start with:
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%28-x%29%2F3=3+
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When you replace x with -9 it becomes:
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%28-%28-9%29%29%2F3=3+
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The two minus signs in the numerator on the right side combine to be a + sign and the
equation is then:
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9%2F3=3+
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And when you divide out the left side the result is:
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3+=+3
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which is true. Therefore, x = -9 is the correct answer.
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Hope this helps you to find your mistake.
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