the area of the top faces of a cube is 9 square centimeters. Use 9 of these cubes to make a rectangular prism. what is the voulme of the rectangular prism

Respuesta :

Answer:

The volume of the rectangular prism is 243 cm³

Step-by-step explanation:

* Lets explain how to solve the problem

- The top face of the cube has an area of 9 cm²

∵ All the faces of the cube are squares

∴ The top face is a square

∵ Area of any square = L² , where L is the length of the side of

  the square

∵ Area of the top face is 9 cm²

∴ L² = 9 ⇒ take √ for both sides

L = 3 cm

∵ The volume of any cube = L³

∵ L = 3 cm

The volume of the cube = (3)³ = 27 cm³

- We will use 9 cubes to make a rectangle prism

∴ The volume of the rectangle prism is equal to the volume of

  the 9 cubes

∴ The volume of the prism = 9 × volume of a cube

∵ The volume of the cube is 27 cm³

∴ The volume of the prism = 9 × 27 = 243 cm³

* The volume of the rectangular prism is 243 cm³

Answer:

The volume of the rectangular prism is 243 cm³.

Step-by-step explanation:

It is given that the area of the top faces of a cube is 9 square centimeters.

The area of a square is

[tex]A=a^2[/tex]

Substitute A=9 to find the edge of the cube.

[tex]9=a^2[/tex]

Taking square root both sides.

[tex]\sqrt{9}=a[/tex]

[tex]3=a[/tex]

The edge of the cube is 3 cm.

The volume of a cube is

[tex]V=a^3[/tex]

The volume of cube is

[tex]V=(3)^3=27[/tex]

The volume of a cube is 27 cm³.

It is given that 9 of these cubes are used to make a rectangular prism.

The volume of the rectangular prism is

[tex]V=9\times (\text{Volume of a cube})[/tex]

[tex]V=9\times 27[/tex]

[tex]V=243[/tex]

Therefore the volume of the rectangular prism is 243 cm³.