1. ## Triangle hydrostatic force!

A triangular plate with height 4 ft and a base of 5 ft is submerged vertically in water so that the top is 2 ft below the surface. Express the hydrostatic force against one side of the plate as an integral and evaluate it. (Give your answer correct to the nearest whole number.)

Thanks! I don't know what to do at all, by the way, all I know is that I need the area and pressure. There's a picture of it of a triangle suspended in a square, and the hypotenuse side is facing the lower right.

2. Is the diagram I have what you mean?.

If so, we can use similar triangles:

$\displaystyle \frac{w(x)}{5}=\frac{6-x}{4}$

$\displaystyle w(x)=\frac{5}{4}(6-x)$

You did not state your weight density of the fluid. You can put that in.

$\displaystyle \int_{2}^{6}x\left(\frac{5}{4}(6-x)\right)dx$

3. Oh thanks!! They didn't give the density, but I think since we are in feet, I need to use 62.5 as the density, Im not too sure on the units. Also, where should I put that? I can pull it out in the front, right? Thank you!

4. Yeah, you just multiply by that. It's a constant.

5. Okay, thanks!!!