(3/7x + 4/7) - (1/3x -1/2)

Different forms of answer: 

2/21x + 15/14

As a single fraction:

2/21x + 15/14 Find common denominator

(2/21x)*(2/2) + (15/14)*(3/3)

4/42x + 45/42

(4x+45)/42

4x + 45

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     42

(3/7x + 4/7) - (1/3x -1/2) Combine Like Terms

3/7x + 4/7 - 1/3x +1/2

2/21x + 15/14

(3/7x + 4/7) - (1/3x -1/2)

You can do this on the web2 calc.  I will put it straight into the calculator here :)

((2*x)/21)+(15/14) = ((2*x)/21)+(15/14)