SOLUTION: can you help me solve this problem 12 5  +  = 1 3x-2 x+4

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Question 77061: can you help me solve this problem
12 5
 +  = 1
3x-2 x+4

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
:
12%2F%28%283x-2%29%29 + 5%2F%28%28x%2B4%29%29 = 1
:
Multiply equation by (3x-2)(x+4) to get rid of the denominators, you then have:
12(x+4) + 5(3x-2) = (3x-2)(x+4)
:
12x + 48 + 15x - 10 = 3x^2 + 10x - 8
:
27x + 38 = 3x^2 + 10x - 8
:
0 = 3x^2 + 10x - 27x - 8 - 38
:
A quadratic equation:
3x^2 - 17x - 46 = 0
:
Factors to:
(3x-23)(x+2) = 0
:
3x = 23
x = 23/3
and
x = -2
:
:
Check solution using -2:
12%2F%28%283%28-2%29-2%29%29 + 5%2F%28%28-2%2B4%29%29 = 1
12%2F%28%28-8%29%29 + 5%2F%28%282%29%29 = 1
-1.5 + 2.5 = 1, proves our solution of -2,
:
I checked the x = 23/3 solution, using decimals on a calc. Anyway, did the
method make sense to you?