SOLUTION: An open rectangular tank is made from a steel plate of area 1440msquared. Its length is twice its width. If the dept of the tank is 4m lesth than the width, find the length of the

Question 785437: An open rectangular tank is made from a steel plate of area 1440msquared. Its length is twice its width. If the dept of the tank is 4m lesth than the width, find the length of the tank.
Answer by KMST(5328) (Show Source): You can put this solution on YOUR website!
= width in meters
= length in meters
= depth in meters

Obviously, the entire 1440m^2 of the steel plate will be used, without wasting any, or stetching/deforming the material.
That is probably far from realistic, but this is just a math problem.
We cannot expect to work on the design, because we have not given enough information. The design is someone else's problem.

The total surface of the tank includes the bottom, ,
and the sides, .
Our equation is

Since L and W came expressed in terms of W, we can substitute those expressions to get an equation in terms of W only:

Dividing both sides of the equal sign by 8, we get

Factoring, we get
with solutions and
We throw away because the width in meters cannot be a negative number.
-->
The length of the tank is
RELATED QUESTIONS
The area of a rectangular floor is 105 square feet. if its length is 1 more than twice... (answered by fractalier,Boreal)

find the dimensions of an open box whose base is a rectangle whose length is twice its... (answered by ankor@dixie-net.com)

The area of a rectangular floor is 72m square. If its width is half of its length, find... (answered by ayhanca)

a rectanlge has an area of 50cm2, if its length is twice its width, find the perimeter (answered by Menjax)

The length of a rectangular piece of carpet is 5 meters less than twice its width. Find... (answered by josmiceli)

a rectangular room has an area of 665 square feet. Its length is three less than twice... (answered by drj)

The length of a rectangular garden is 10 meters more than twice its width. If the area of (answered by jorel555)

A rectangular tank with a square base, an open top, and a volume of 13,500 ft3 is to be... (answered by josgarithmetic,ikleyn)

The length of a rectangular carpet is 4 feet greater than twice its width. if the area is (answered by nyc_function)