SOLUTION: Find all solutions by factoring. {{{2x^2+45=x^2+14x}}}

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Question 44674: Find all solutions by factoring.
2x%5E2%2B45=x%5E2%2B14x
Answer by adamchapman(301) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2%2B45=x%5E2%2B14x
Rearrange to get zero on the right-hand side:
x%5E2%2B45=14x
x%5E2-14x%2B45=0
Now you have a quadratic expression, which can be solved using the quadratic solver x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29+ where
a=1
b=-14
c=45.
Plug these values into the solver to get:
x+=+%2814+%2B-+sqrt%28+14%5E2-4%2845%29+%29%29%2F2+
x+=+%2814+%2B-+sqrt%28+14%5E2-180+%29%29%2F2+
x+=+%2814+%2B-+sqrt%28+196-180+%29%29%2F2+
x+=+%2814+%2B-+sqrt%28+16+%29%29%2F2+
x+=+%2814+%2B-+4%29%2F2+
x+=+7+%2B-+2+
so the two solutions are x=5 or x=9.
I hope this helps.
P.S. I am trying to start up my own homework help website. I would be extremely grateful if you would e-mail me some feedback on the help you received to adam.chapman@student.manchester.ac.uk
Adam