The volume of a box is #2x^3+9x^2-20x-75# cubic centimeters. Find the length if width is #(x+5)# centimeters and the height is #(x-3)# centimeters? Can you please show the work. Thank you

2 Answers
Apr 13, 2017

I got #2x+5#

Explanation:

Have a look:
enter image source here

Apr 14, 2017

#color(red)(2x+5#

Explanation:

Volume of box# = 2x^3+9x^2-20x-75##cm^3# given

Width#=x+5# cm given

Height#=x-3# cm given

Length?

#:.W xx H xx L=#Volume

#:.L=(Volume)/(W xx H)#

#:.W xx H=(x-3)*(x+5)=x^2+2x-15#

#:.L=(2x^3+9x^2-20x-75)/(x^2+2x-15)#

#color(white)(000000000000")")underline(color(white)(0000000000000)color(red)(2x+5color(white)(0000))#
#x^2+2x-15color(white)(0)")"color(white)(0)2x^3+9x^2-20x-75#
#color(white)(000000000000")"0)underline(2x^3+4x^2-30x)#
#color(white)(00000000000000000")"00)5x^2+10x-75#
#color(white)(00000000000000000")"00)underline(5x^2+10x-75)#

#color(white)(00000")"000)color(red)(2x+5##=#quotient#=#Length