SOLUTION: explain me how to fin the lenght, width, and height this is the information they gave me. the area of the base of the box is 20 square inches the perimeter of the base of the box

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Question 558486: explain me how to fin the lenght, width, and height this is the information they gave me.
the area of the base of the box is 20 square inches
the perimeter of the base of the box is 18 inches
the volume of the box is 160 cubic inches

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
fin the lenght, width, and height this is the information they gave me.
Write an equation for each statement:
:
"the area of the base of the box is 20 square inches"
L * W = 20
:
"the perimeter of the base of the box is 18 inches"
2L + 2W = 18
simplify, divide by 2
L + W = 9
L = (9-W)
:
Replace L with (9-W) in the area equation
W(9-W) = 20
-W^2 + 9W = 20
0 = W^2 - 9W + 20; a quadratic equation, that will easily factor to:
(W-4)(W-5) = 0
two solutions
W = 4, then L = 5
W = 5, then L = 4
:
"the volume of the box is 160 cubic inches"
Find the height by dividing the volume by the area of the base (20)
160%2F20 = 8 inches is the height
;
;
The dimensions of the box 5 by 4 by 8