SOLUTION: the additve inverse of a number divided by twelve is the same as one less than three times its reciprocal.

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Question 134556: the additve inverse of a number divided by twelve is the same as one less than three times its reciprocal.
Found 2 solutions by solver91311, ankor@dixie-net.com:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
if a is the number, then the additive inverse is -a and its reciprocal is 1%2Fa. "is the same as" means "equals"

The additive inverse of a number (-a), divided by 12 (-a%2F12) is the same as (=) one less than (-1) three times its reciprocal (3%2A%281%2Fa%29=3%2Fa). Put it all together:

-a%2F12=%283%2Fa%29-1

Add 1 to both sides:
1-a%2F12=3%2Fa

LCD on the left is 12, so:
%2812-a%29%2F12=3%2Fa

Cross-multiply (numerator on the left times denominator on the right equals denominator on the left times numerator on the right)
a%2812-a%29=36

12a-a%5E2=36
-a%5E2%2B12a-36=0

Multiply by -1:
a%5E2-12a%2B36=0

Trinomial is a perfect square:
%28a-6%29%28a-6%29=0

Hence a=6

Check:
-%286%29%2F12=%283%2F6%29-1
-1%2F2=1%2F2-1=-1%2F2 Answer checks.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
the additive inverse of a number divided by twelve is the same as one less than three times its reciprocal.
:
Let x = a number
then
-x = additive inverse of a number
:
Write an equation for the statement:
"the additive inverse of a number divided by twelve is the same as one less than three times its reciprocal."
%28-x%29%2F12 = 3%2Fx - 1
Multiply equation by 12x to get rid of the denominators, and you have:
x(-x) = 12(3) - 12x
:
-x^2 = 36 - 12x
:
Arrange as a quadratic equation:
x^2 - 12x + 36 = 0
Factors to
(x-6)^2 = 0
x = +6
:
Check solution in original equation:
%28-6%29%2F12 = 3%2F6 - 1
-1%2F2 = 1%2F2 - 1; confirms our solution