SOLUTION: solve 3n^2-2n-5=0

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Question 449322: solve 3n^2-2n-5=0
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

+3n%5E2-2n-5=0...use quadratic formula
n+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ....notice that a=3, b=-2 and c=-5

n+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A3%2A%28-5%29+%29%29%2F%282%2A3%29+

n+=+%282+%2B-+sqrt%28+4%2B60+%29%29%2F6+

n+=+%282+%2B-+sqrt%28+64+%29%29%2F6+

n+=+%282+%2B-+8%29%2F6+
so, solutions are:

n+=+%282+%2B+8%29%2F6+
n+=+10%2F6+
n+=+5%2F3
n+=+1.7

or
n+=+%282+-+8%29%2F6+
n+=+-6%2F6+
n+=+-1

let's see it on a graph:
+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+3x%5E2-2x-5%29+