Michelle is saving $20 each week for a bike of her dreams. how long until she can purchase her bike

Let x represent the amount of weeks she is saving up for the bike, and y represents the cost of the bike.

The equation would look like this:

y = 20x

So, let's say the bike costs $2000.

2000 = 20x

Divide 2000 by 20, and it will give you the x value (or, the amount of weeks it will take)

100 = x

It will take 100 weeks for her to save $2000 for the bike, if she puts back $20 each week.