The key point to remember when dealing with an algebra equation is that whatever operation you carry out on one side of the equation, you MUST do to the other side as well.
To solve this equation, we first want to collect like terms onto one side of the equation, in this case the 'x' terms. To do this, we will subtract the '3x' term from BOTH sides of the equation:
5x-3x-6=7
To complete the process of collecting like terms, we now need to add '6' to both sides of the equation, so that we are left with only 'x' terms on the left hand side :
5x-3x=7+6
Now that we have collected all like terms, we can simplify the equation, which becomes:
2x=13
Finally, to solve the equation, we want to find the value of 'x' on its own. We have the value for 2x, so we can divide BOTH sides of the equation by 2 to solve for x:
x=13/2 or x=6.5