Question 384208
Let h = number of hundred dollar bills
Let t = number of twenty dollar bills

the equation is:


100h + 20t = 400


Image that h is like the y-variable, and t is like the x-variable.

The graph would look like this: http://www.wolframalpha.com/input/?i=100y+%2B+20x+%3D+400
(copy this link into your web browser)


Try plotting this graph yourself on graph paper, and you should see a variety of combinations that are possible. Anything that falls on the line is possible.


For instance, if h=3, then t=5.

This makes sense because 100(3) + 20(5) = 400


Another possibility is if h=2, then t=10.

100(2) + 20(10) = 400


I will leave it up to you to find the last combination. Hint... keep going down the line as I've done.