The volume of Olivia's rectangular lunchbox is 240 cubic inches. The lunchbox is 3 inches deep, and it's length is 2 inches more than its width. how wide is Olivia's lunchbox
Answers
Answered by
18
dimensions of the lunch box are
depth = h= 3 inches
let width = w= x inches
length =l = 2 inches more than its width
l=( 2+x) inches
volume of the lunch box = 240 cubic inches
lwh = 240
(2+x)* x*3 =240
(2+x)x=240/3
2x+x²=80
x²+2x-80=0
x²+10x-8x-80=0
x(x+10)-8(x+10)=0
(x+10)(x-8)=0
∴x+10 =0 or x-8 =0
x=-10 or x=8
but x should not be negative
∴width of the lunch box = w= x= 8 inches
depth = h= 3 inches
let width = w= x inches
length =l = 2 inches more than its width
l=( 2+x) inches
volume of the lunch box = 240 cubic inches
lwh = 240
(2+x)* x*3 =240
(2+x)x=240/3
2x+x²=80
x²+2x-80=0
x²+10x-8x-80=0
x(x+10)-8(x+10)=0
(x+10)(x-8)=0
∴x+10 =0 or x-8 =0
x=-10 or x=8
but x should not be negative
∴width of the lunch box = w= x= 8 inches
Similar questions