To solve this problem, you first must put it into an equation (without words).
The difference between 7 and x would equal to:
7 - x
The word "is" means ( = ), so you put an equal sign right next to the term 7-x:
7 - x =
Then, simply put the 23 on the right of the equal sign. Your equation should look like this:
7 - x = 23
Now solve the equation.
7 - x = 23
-x = 16 subtract 7 from both sides of the equation
x = -16 divide by -1 on both sides of the equation to isolate x
Your final answer is -16.