[Xenus]

Math help. I have an issue I am tring to find the height of water rising in a pool. What is the area of a trapizoid expressed by a function of h or hieght I cannot seem to get it. I have (((b1+b2)h)/2)w)

[Vadi]

Isn't that A=((a+c)/2)*h ? (a,c ... parallel sides)

[OpenGL guy]

Originally Posted by Xenus

Math help. I have an issue I am tring to find the height of water rising in a pool. What is the area of a trapizoid expressed by a function of h or hieght I cannot seem to get it. I have (((b1+b2)h)/2)w)

What's the "w" for? If you want area of a trapezoid, it's just A = (b1 + b2)*h/2. You have to know b1 and b2 and A to compute h.

[Xenus]

I'm trying to find the volume of a trapzoidal swimming pool. w is the width of the pool.


If the pool is being filled at a rate of 1.2 cubic feet per minute, how fast is the water level rising when the depth of water is 5 feet?
We first need to express the volume of water in the pool as a function of , the depth of water in the pool. We find that

Calculus trying to find the rate the water is rising at.

b2 is dependant on h and since at when h =7 b2 =24 = 24h=7b2 b2=(24/7)h but it still doesn't appear to be right.

got it it is actually 16(12h+6/7h^2)

[Xenus]

Does anyone know how to do realted rates on a clock at 10 o'clock. the minute hand is 5 cm and the hour hand is 3 cm? I get dh/dt=(5(2pi)+3(pi/6)+15sin(-pi/6)(11pi/6))/(5.830951895)

[OpenGL guy]

Originally Posted by Xenus

I'm trying to find the volume of a trapzoidal swimming pool. w is the width of the pool.


If the pool is being filled at a rate of 1.2 cubic feet per minute, how fast is the water level rising when the depth of water is 5 feet?
We first need to express the volume of water in the pool as a function of , the depth of water in the pool. We find that

Calculus trying to find the rate the water is rising at.

b2 is dependant on h and since at when h =7 b2 =24 = 24h=7b2 b2=(24/7)h but it still doesn't appear to be right.

got it it is actually 16(12h+6/7h^2)

You didn't give us the full problem! But I don't think your answer is correct as w is not a part of the result. For example, if w = 0.000001 ft, then the level will rise very fast, but if w = 100000 ft then the level will rise very slow.

Unless w is one of those other things you didn't tell us

[Xenus]

Originally Posted by OpenGL guy

You didn't give us the full problem! But I don't think your answer is correct as w is not a part of the result. For example, if w = 0.000001 ft, then the level will rise very fast, but if w = 100000 ft then the level will rise very slow.

Unless w is one of those other things you didn't tell us

Oh I know that is right the webwork said so. The width was 16 an the bottom base was 12 the 2 sides were only 6 each and I would of got it faster by using the equal triangle form.

[Xenus]

Now can you check my last question.

Does anyone know how to do realted rates on a clock at 10 o'clock. the minute hand is 5 cm and the hour hand is 3 cm? I get dh/dt=((5)(2pi)+(3)(pi/6)-((2pi)(3)cos(-pi/3))+5(((pi/6)cos(-pi/3))-3sin(-pi/3)(11pi/6)))/(5.830951895)

[Xenus]

If somebody could please help that would be great I've done the prob a million times and find ways to get lots of different answers just messing with the prenthesises but none are right so far. I"ve only got 25 minutes left.

Oh well it's two late now and I spent about 8hours getting an 89% on the homework.