width=x
length = 2x (2 times the width)
depth = x-2
volume = l*w*d = 64 in^3
x*2x*(x-2)=64
2x^2*(x-2)=64
2x^3-4x^2-64=0
I got x = 4 after some guessing
check: http://www.wolframalpha.com/input/?i=2x%5E3-4x%5E2-64+%3D+0
I agree with you answered for 1 and 2nd part.
A jewelry box is designed such that its length is twice its width and its depth is 2 inches less than its width. The volume of the box is 64 cubic inches.
Use synthetic division to find the roots of the polynomial equation. Are the roots all rational numbers?
Ans: Yes, the only root 4 is rational.
What are the dimensions of the box?
Ans: width is 4, depth is 2 and length is 8.
1 answer
1 answer