SOLUTION: how do u do 5n^2-7n+2=0

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Question 419342: how do u do 5n^2-7n+2=0
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

factoring

 5n^2-7n+2=0     an^2 + bn + c

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

n+=+%287+%2B-+sqrt%289+%29%29%2F%2810%29+

n+=+%287+%2B-+sqrt%289+%29%29%2F%2810%29+

n+=+%287+%2B-+3%29%2F%2810%29+

   n = 10/10 = 1  and n = 4/10 = 2/5

 5(n-1)(n-2/5) = 0

Note:SUM of the inner product(-n) and the outer product(-2/5n) = -7/5n

                                                     5*-7/5n = -7n