SOLUTION: the sum of a number and 8 times its reciprocal is -9

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Question 370163: the sum of a number and 8 times its reciprocal is -9
Found 3 solutions by Fombitz, lefty4ever26, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
N%2B8%2FN=-9
N%5E2%2B8=-9N
N%5E2%2B9N%2B8=0
%28N%2B1%29%28N%2B8%29=0
Two solutions:
N%2B1=0
highlight%28N=-1%29
.
.
N%2B8=0
highlight%28N=-8%29

Answer by lefty4ever26(59) About Me  (Show Source):
You can put this solution on YOUR website!
x%2B8%281%2Fx%29=-9 Equation.
x%2B8%2Fx=-9 Multiply both sides by x to cancel the fraction.
x%5E2%2B8=-9x Add 9x to both sides.
x%5E2%2B9x%2B8=0 Factor.
%28x%2B1%29%28x%2B8%29=0 Set factors equal to 0 and solve for x.
x%2B1=0 x%2B8=0
x=-1 x=-8
Your number can be either -1 or -8

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,

Let x represent the number

Write as we Read

x +  8*(1/x) = -9

x^2 + 8 = -9x

x^2 + 9x + 8 = 0

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

x+=+%28-9%2B-+sqrt%2849%29%29%2F%282%29+

x+=+%28-9%2B-+7%29%2F%282%29+

x = -16/2 = -8

x = -2/2 = -1

checking our answers

-8 + 8*(-1/8) = -9

-1 + 8*-1 = -9