The LCD is 12x(x+1). Put that over 1, like this
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:
Distribute:
Combine like terms on the left:
Swap sides to get the x² term on the left
Subtract the entire right side from both sides to get 0 on the right
That factors as
Edwin