SOLUTION: r^2-10=3r solve for factoring?

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Question 260355: r^2-10=3r solve for factoring?
Found 2 solutions by drk, richwmiller:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
Here is the original equation:
(i)r%5E2-10=3r
step 1 - set = 0.
(ii) r%5E2-3r+-+10+=+0
step 2 - factor to get
(iii) %28r-5%29%28r%2B2%29=0
step 3 solve each parenthesis for r to get
r-5 = 0
r = 5
r+2 = 0
r = -2

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
r^2-3r-10=0
we want factors of 10 that differ by 3
5 and 2 seem perfect
(r-5)(r+2)=0