SOLUTION: The square of one more than number x is 13 more than itself. Find the value of x where x is positive.

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Question 1036358: The square of one more than number x is 13 more than itself. Find the value of x where x is positive.
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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%28x%2B1%29%5E2=x%2B13
x%5E2%2B2x%2B1=x%2B13
x%5E2%2Bx-12=0
%28x%2B4%29%28x-3%29=0
x%2B4=0 OR x-3=0
x=-4 OR x=3
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Since x=-4 is not positive, then answer is x=3.
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CHECK:
For x=3:
%28x%2B1%29%5E2=x%2B13
%283%2B1%29%5E2=3%2B13
4%5E2=16
16=16
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