Solve this equation; 5x - 4 = 3x + 7

In order to solve equations of x it is necessary to move all the Xs over to one side and the other numbers over to the other side;

5x - 4 = 3x + 7

As 5x is greater than 3x it makes sense to subtract 3x from both sides so that any negative Xs are avoided, this changes the equation to:

2x - 4 = 7

The next step is to add 4 to both sides to cancel out the -4 on the left hand side;

2x = 11

Finally dividing both x and 11 by 2 will give the value of x; 

x = 11/2 or x = 5.5

*A key thing to remember when solving equations is whatever you do to one side you MUST do to the other, e.g. if you divide one side by 3 you must divide the other side by 3, or if you add 6 to one side you must add 6 to the other side. This ensures that the equation stays correct as both sides continue to equal each other.