length --- x
width ---- x
height ---- x+5
x(x)(x+5) = 72
x^3 + 5x^2 - 72 = 0
I tried ±2, and ±3
x = 3 works
so by synthetic long division
x^3 + 5x^2 - 72 = 0
(x-3)(x^2+ 4x + 24) = 0
the quadratic has no real solution, so
x = 3
the prism is 3 by 3 by 8
the length of a rare jeweled rectangular prism has a length equal to its width and a height that is 5 cm greater than its width.volume of the prism is 72 cc
a) write a polynomial equation that can be used to solve for the width (x) of the prism
b) solve the equation. what are the actual dimensions of the prism?
1 answer
1 answer