Question

When a person swims underwater, the pressure in his or her ears varies directly with the depth at which he or she is swimming.
Write an equation of direct variation that represents the situation.
Help!

Answer 1

This is all i know! :(

Answer 2

So it looks like that the deeper you go, the greater the pressure correct?

Answer 3

Yeah

Answer 4

This is direct variation. The the y axis increases with the x. This means that the equation we are looking at is a linear function.

Answer 5

Yes but with this problem how do i figure out how to write the equation?

Answer 6

So the basic structure of a linear function is y=bx+c. We are given no data concerning at what depth the swimming starts, so we will assume that the depth is 0, meaning that c is 0, and inconsequential. the function is now y=bx. B is slope. If the x axis is depth and the y axis is pressure, we can use the picture to determine the slope. Do you know how to do this?

Answer 7

I think so would the answer be y=4.3x or y=(4.3/10)x

Answer 8

It would be 4.3/10 because the slope is rise/run, meaning you have to include the 10