how do i find the length of a rectangle when the area is
(R cubed-24R-5) cm sqaured
and the width is
(R-5)cm
???
Since Area = l x w
and we know the area and width
r^3 - 24r - 5 = l(r-5)
l = (r^3 - 24r - 5)/(r-5)
I noticed that when r=5, r^3 - 24r - 5 = 0
so the division will be exact
by synthetic division or by algebraic long division
l
= (r^3 - 24r - 5)/(r-5)
= r^2 + 5r + 1