You have a block of wood with a depth of x units, a length of 5x units, and a height of 2x units. You need to cut a slice off the top of the block to decrease the height by 2 units. Th e new block will have a volume of 480 cubic units. a. What are the dimensions of the new block?

Respuesta :

Answer:

[tex]Depth = x= 4 units[/tex]

[tex]length = 5x= 5(4)= 20 \ units[/tex]

[tex]height = 2x-2= 2(4)-2= 6 \ units[/tex]

Step-by-step explanation:

You have a block of wood with a depth of x units, a length of 5x units, and a height of 2x units.

height is decreased by 2 units , so height becomes 2x-2

Volume of a block is length times width time height

[tex]volume = x \cdot 5x \cdot (2x-2)[/tex]

[tex]480 = 10x^3-10x^2[/tex]

divide whole equation by 10

[tex]48= x^3-x^2[/tex]

Subtract 48 from both sides

[tex]x^3-x^2-48=0[/tex]

[tex]\left(x-4\right)\left(x^2+3x+12\right)=0[/tex]

[tex]x-4=0[/tex], x=4

[tex]Depth = x= 4 units[/tex]

[tex]length = 5x= 5(4)= 20 \ units[/tex]

[tex]height = 2x-2= 2(4)-2= 6 \ units[/tex]