SOLUTION: Hi, I have to solve the following equation for x log(98-x+x^2)=2 thanks for the help!

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Question 50658: Hi, I have to solve the following equation for x
log(98-x+x^2)=2
thanks for the help!
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
This is assumed to be log base 10, so it can be written as
log+%2810%2C+98-x%2Bx%5E2%29+=+2
This means that 10%5E2+=+98-x%2Bx%5E2
100=98-x%2Bx%5E2

Set equal to zero by subtracting 100 from each side:
100-100=98-100-x%2Bx%5E2
0+=+x%5E2+-x+-2
0=+%28x-2%29%28x%2B1%29
x=2 or x=-1

You must reject x = -1, since you cannot have a log of a negative!!
Final answer is x = 2. By the way it checks:
log%2810%2C+%2898-2%2B4%29%29+=+log%2810%2C+100%29+=+2

R^2 at SCC