SOLUTION: 2r2-3r-1=0

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Question 751432: 2r2-3r-1=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Use the quadratic formula to solve for r

r+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29

r+=+%28-%28-3%29%2B-sqrt%28%28-3%29%5E2-4%282%29%28-1%29%29%29%2F%282%282%29%29 Plug in a+=+2, b+=+-3, c+=+-1

r+=+%283%2B-sqrt%289-%28-8%29%29%29%2F%284%29

r+=+%283%2B-sqrt%289%2B8%29%29%2F%284%29

r+=+%283%2B-sqrt%2817%29%29%2F4

Exact Solutions: r+=+%283%2Bsqrt%2817%29%29%2F4 or r+=+%283-sqrt%2817%29%29%2F4

Approximate Solutions: r+=+1.780776 or r+=+-0.280776