I you are to buy a magazine (it says in the question that you only bought one) you then know to subtract $5 from the total $24 dollars spent. Now you have $19 dollars left to see how many notebooks you can buy at the most. 19 divided by 4 ($4 each for the notebooks) you get 4.75 or 4 notebooks like 0.75 does not count as a full notebook.
I am not learning about inequalities, so the answer below is my best guess of an inequality for this:
4x-4=$24 (Even though it says 4, I know the 5 above was a typo)
Please comment on my answer if you want me to edit or elaborate. I am just trying to help, not steal your points.
The product of the slopes would be -1 because the slopes of two lines that are perpendicular are opposite reciprocals (ex. 2 and -1/2 multiplied together would be -1)
