SOLUTION: equations transformable to quadratic equation: i dont get thisone can you please help.. 1/x + 1/(x+1) = 7/12

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Question 1143445: equations transformable to quadratic equation:
i dont get thisone can you please help..
1/x + 1/(x+1) = 7/12

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
1%2Fx+%2B+1%2F%28x%2B1%29+=+7%2F12

The LCD is 12x(x+1).  Put that over 1, like this red%28%2812x%28x%2B1%29%29%2F1%29

Multiply every term on both sides by it, like this:



Then cancel like this:



and what's left is



We don't need to write the 1's in the denominators, so we have:

12%28x%2B1%29%2B12x=7x%28x%2B1%29

Distribute:

12x%2B12%2B12x=7x%5E2%2B7x

Combine like terms on the left:

24x%2B12=7x%5E2%2B7x

Swap sides to get the x² term on the left

7x%5E2%2B7x=24x%2B12

Subtract the entire right side from both sides to get 0 on the right

7x%5E2-17x-12=0

That factors as

%287x%2B4%29%28x-3%29=0




Edwin