They are all number with letters in the front
The center line that goes from left to right is your x axis and the line that goes from top to bottom is you y axis
"The sum of a number and 7"
Sum implies addition.
We would write this part as <em>n + 7</em>.
Then we would write the "9 times" part in like this:
<em>9 </em><em>·</em><em> </em><em>(n + 7)</em><em>
</em>We can't write just 9 · n + 7 without the parentheses, because then we would be multiplying just 9 and n instead of 9 and the sum of n and 7. (order of operations says we must do multiplication first)
