Posted by **John** on Tuesday, September 18, 2012 at 8:28am.

Please help I have no Idea what to do here.

A box with an open top is to be constructed by cutting a-inch squares from the corners of a rectangular sheet of tin whose length is twice its width. What size sheet will produce a box having a volume of 420 in^3 when a = 3?

- Math -
**Reiny**, Tuesday, September 18, 2012 at 8:57am
You are cutting out 3-inch squares at the four corners.

Make a diagram.

width of base ---- x inches

length of base --- 2x inches, (you said so)

height of box ---- 3 inches

(x-6)(2x-6)(3) = 420

(x-6)(2x-6) = 140

x^2 - 18x + 36 = 140

2x^2 - 18x - 104 = 0

x = (18 ± √1156)/4

= (18 ± 34)/4

= 13 inches or a negative

so the sheet must have been 13 inches by 26 inches

## Answer this Question

## Related Questions

- Math - A box with an open top is to be constructed by cutting a-inch squares ...
- Calculus - an open top box is to be made by cutting congruent squares of side ...
- Calc - a box with an open top is to be made from a rectangular piece of tin by ...
- math.....need help - Solve the problem. An open box is to be made from a ...
- math - open top rectangular box made from 35 x 35 inch piece of sheet metal by ...
- Calculus - An open top box is made by cutting congruent squares from the corners...
- algebra - Open-top box. Thomas is going to make an open-top box by cutting equal...
- Math - An open box is to be made from a 11 inch by 11 inch piece of cardboad. ...
- Math - A box with no top is to be constructed from a piece of cardboard whose ...
- pre-calc - A box with an open top is to be constructed by cutting equal-sized ...

More Related Questions