Question 283644
To solve this equation:  4x + 9 = 7x

You can determine that since there are 2 x's in this equation, they can be combined together, they are like terms.
 
First, get the x's together by subtracting the 4x from the left to the right side of the equation:

{{{4x + 9 = 7x}}}
{{{9 = 7x - 4x}}}

{{{9 = 3x}}}

Now divide by 3 to both sides of the equation to get x by itself:

{{{3x = 9}}}
{{{3x/3 = 9/3}}}
{{{x = 3}}}