Find the volume of the pie dish

[Painguy]

Homework Statement

A pie dish is 9 inches across the top, 7 inches across the bottom, and 2.4 inches deep. See the figure above. Compute the volume of this dish. Give your answer correct to 2 decimal places.

Homework Equations

The Attempt at a Solution

y=2.4
x=+-3.5, +-4.5

I'm unsure what to do from here. I'm assuming we are rotating about the y-axis.
y=4.5x/3.5-2.98571

∫pi(3.5/4.5(y+2.98571))^2-pi(4.5)^2 dy

I'm not entirely sure what to do. The above expression is obviously wrong, but that's all I could come up with. What exactly am I doing wrong?

 

[Mark44]

Homework Statement

A pie dish is 9 inches across the top, 7 inches across the bottom, and 2.4 inches deep. See the figure above. Compute the volume of this dish. Give your answer correct to 2 decimal places.

Homework Equations

The Attempt at a Solution

y=2.4
x=+-3.5, +-4.5

I'm unsure what to do from here. I'm assuming we are rotating about the y-axis.
y=4.5x/3.5-2.98571

How did you get this?

Have you drawn a sketch of the region that will be rotated?

Assuming that the bottom of the pan is on the x-axis, find the equation of the line between (3.5, 0) and (4.5, 2.4). That line will be the right boundary of the region.

∫pi(3.5/4.5(y+2.98571))^2-pi(4.5)^2 dy

I'm not entirely sure what to do. The above expression is obviously wrong, but that's all I could come up with. What exactly am I doing wrong?