Question 320329
Hi, 
I'll help you with the first one and let's see if you can do the others. Deal?
x/3=4/x+1 
Multiply both sides by 3(x+1) to get:
x(x+1)=3(4)
Rewritten as:
x^2+x=12
Subtract 12 from both sides to get:
x^2+x-12=0
Now factor toget:
(x+4)(x-3)=0
Solve for x results in:
x=-4
x=3 
We can plug these answers into the original problem to see if they are correct. 
Make sense?
RJ 
www.math-unlock.com