Inverse Relationship

The Cordova family is planning a trip of 300 miles to Mackinac Island, near the upper peninsula of Michigan.  Mr. Cordova does some calculations to see how the travel time will change if the family drives at different average speeds.

Date	Notes	Travel Time
February 15	Traveled by plane	1.5 hours
May 22	Drove	10 hours
July 3	Drove - stopped for repairs	14 hours
November 23	Flew - flight delayed	4 hours
December 23	Took overnight train	18 hours

We noticed:

As y gets bigger, x gets smaller

We are trying to decide an equation:

L x W=Area (First problem about the rectangle) L x W= 24

X + Y= coordinates

Travel Time x Coordinates

Maybe  one equation-multiple formats

Maybe multiple equations

We got this by using the X and Y variables to generalize them. ( for L x W could do X x Y= 24)

X x Y=Z

Now we have: 

X x Y= 24

x x y=500

What is Z? What is Z going to be for the inverse relationship? 

Class idea: x and y are variables and can change. Z is going to be constant that doesn't change.

We have x and y= some kind of a constant (class thinks it should be Z)