Question

3x/x+1=12/xx-1+2

Answer 1

Your questions have gone unanswered because it's pretty clear you have made no attempt on your own.

Once you have shown your work so far, even if it's incomplete, you'll be more likely to get good responses.

Answer 2

i have 3x/x+1=12/x^2-1+2
ans. 3x/x+1=14/x^2-1
3/1=14/x^-1
14/3x^2-1=14/2x^2
x=7/1
this is the answer that i have

Answer 3

You need to combine like terms. Numerals cannot be combined with X terms.

3x/x+1=12/x^2-1+2

x/x cancel each other out.

3 + 1 = 12/x^2 + 1

Subtract 1 from each side.

3 = 12/x^2

Multiply both sides by x^2.

3x^2 = 12

Divide both sides by 3.

x^2 = 4

x = 2

Possibly these sources might help:

http://www.algebrahelp.com/lessons/simplifying/oops/
http://northpark.edu/math/PreCalculus/rules.html
http://mathforum.org/dr.math/faq/faq.order.operations.html

Use the same principles in your other problems. I hope this helps. Thanks for asking.