SOLUTION: use the quadratic formula to solve (r-3)(r+5)=2

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Question 379042: use the quadratic formula to solve
(r-3)(r+5)=2
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,

using the quadratic formula to solve

(r-3)(r+5)=2

r^2 +2r - 15 = 2

r^2 +2r - 17 = 0

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-2+%2B-+sqrt%28+72+%29%29%2F%282%29+

x+=+%28-2+%2B-+sqrt%28+72+%29%29%2F%282%29+

x+=+%28-2+%2B-+sqrt%28+36%2A2+%29%29%2F%282%29+

x+=+%28-2+%2B-+6%2Asqrt%28+2+%29%29%2F%282%29+

x+=+%28-1+%2B-+3%2Asqrt%28+2+%29%29