With multiple fractions i look for what the common denominator would be and multiply by it 1/3 + x/4 = 3 Note that 3 and 4 have a common denominator of 12 so we have 12(1/3 + x/4 = 3) then we have 

4+3x=36 Then

3x=32 Then

x=32/3

I agree, multiplying both sides by the denominator is a great way to get rid of the fractions right away. If you have an equation with more than one fraction, you may want to work towards putting the variable terms on the left and the constants on the right.

Here's an example:

1/3 + x/4 = 3

1.) Subtract 1/3 from both sides

x/4 = 2 2/3  (or 2.667 if you're using a calculator :)

2.) Multiply both sides by 4

x = 10 2/3 (or 10.667)

You can multiply both sides of the equation by 2 to remove the fraction. Remember that both terms on the left side must be multiplied by 2. 2(9+ (x/2)) = 2 (7) (2*9) + (2*(x/2)) = 14 18 + x = 14 <-- Now solve for x. 18 + x - 18 = 14 - 18 x = -4