1. You must use the formula for calculate the volume of a rectangular prism, which is:
V=(h)(l)(w)
V: It is the volumen of the rectangular prism (V=1152 inches³).
h: It is the height of the rectangular prism (h=18-w).
l:It is the lenght of the rectangular prism (l=2w+4).
2. When you substitute these calues into the formula, you obtain:
V=(h)(l)(w)
1152=(18-w)(2w+4)(w)
(18-w)(2w+4)(w)-1152=0
3. Then, you should mutiply them:
36w²-2w³+72w-4w²-1152=0
32w²-2w³+72w-1152=0
4. When you factor, you obtain:
2(w-16)(w-6)(w+6)
w1=16
w2=6
w3=-6
5. The problem says that the height is greater than the width, therefore, the widht is:
w=6 inches
6. The length is:
l=2w+4
l=2(6)+4
l=16 inches
7. And the height is:
h=18-w
h=18-6
h=12 inches
What are the dimensions of the bag?
The dimensions of the bag are:
l=16 inches
h=12 inches
w=6 inches