Question 280749
Multiply thru by a+1
3a-1=4a+4
-a=5
a=-5
( Get the basics down, go back and review!)
Multiplying both sides by (THE SAME) number does not change the value of the equation.
Immediately we want to multiply by (a+1) to get rid of the fraction.
We then have a nice equation. 
Combine like terms, add.
Presto. (LOL)