Answer:
5c+50
Explanation:
Since Ellen wants to buy 5 videos for c dollars, you would multiply those together, which is 5c, since you don't know what it stands for. You would add the $30 for the DVD and $20 for the CD together, which is 50.
Solving:
Then you eliminate the 5 by dividing 5 by itself, which is 1, so it becomes x by itself. Since you did that to one side, you'll do it to the other. 50 divided by 5 is 10. So therefore, if you were to solve it, then the answer would be 10.