SOLUTION: x^-x-30=0 I need help on how to figure this problem

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Question 282606: x^-x-30=0 I need help on how to figure this problem
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
Assuming you problem is to solve:
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x^2 -x -30 = 0
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Factoring this is the best approach.
We notice that we need a + and a - term to result in -30.
And the two factors need to 1 apart.
There are a number of ways we can multiply two numbers to result in 30.
3*10 = 30, but they are 7 apart.
5*6 = 30, and they are 1 apart. So that's it.
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(x -6)(x +5) = 0
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checking this using FOIL (first, outer, inner, last):
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x*x + x*5 + (-6)x + (-6)*5 = x^2 -x -30.
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So, the solutions that make the equation true are: x=6 and x= -5.
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We also can graph it.
graph%28500%2C500%2C-10%2C10%2C-50%2C50%2Cx%2Ax-x-30%29