Answer:
That is not a function :)
Step-by-step explanation:
You can recognize functions by seeing if it passes the <em><u>vertical line test</u></em><em><u>.</u></em> If you draw a vertical line anywhere are the grid and it crosses the equation in more then one place then it does not pass the test, and is not a function.
Here's an attachment that might help
At the end of Round 3, David's score would be 2000.
Using the given formula T = LS
And given the time is 3 minutes (3 x 60 = 180 seconds)and the speed is 4-1/2 inches per second:
180 = L x 4-1/2
Solve for L by dividing both sides by 4-1/2:
L = 180 / 4-1/2
L = 40
The length should be 40 inches.
<em>x = 1</em>
<em><u>Here is why:</u></em>

Add x to both sides.

Add 5 to both sides.

Divide.
x = 1