11. CCSS Persevere with Problems The figure at the right is made by
placing a cube with 12-centimeter sides on top of another cube
with 15-centimeter sides. Find the surface area of the figure.
12 cm
12 cm
nrism that has
15 cm
15 cm

11 CCSS Persevere with Problems The figure at the right is made by placing a cube with 12centimeter sides on top of another cube with 15centimeter sides Find th class=

Respuesta :

Answer :

  • 1926 cm^2 or 19.26 m^2.

Explanation :

Total surface area of a cube is given by,

  • TSA = 6(a^2)

wherein,

  • a = side of the cube

TSA of cube 1

  • TSA 1 = 6((12cm)^2)
  • TSA 1 = 864 cm^2

TSA of cube 2

  • TSA 2 = 6((15cm)^2)
  • TSA 2 = 1350 cm^2

when one side of a shape is overlapped by another side ,then, that area covered doesn't count in the final surface area , therefore,the area ((12cm)^2)*2 = 288^2 would be negligible.

thus, the total surface area of the figure would be

  • TSA = TSA 1 + TSA 2 - 288 cm^2
  • TSA = 864 cm^2 + 1350 cm^2 - 288 cm^2
  • TSA = 1926 cm^2 or 19.26 cm^2

Answer:

1,926 cm²

Step-by-step explanation:

A cube is a three-dimensional geometric shape composed of six congruent square faces, each with an area equal to the square of the cube's side length.

The given figure is made by placing a cube with 12 cm sides on top of another cube with 15 cm sides.

Therefore, the total surface area of the given figure is made up of:

  • 5 congruent faces of the 12 cm cube.
  • 5 congruent faces of the 15 cm cube.
  • One face of the 15 cm cube less one face of the 12 cm cube.

As the area of one face of a cube is the square of its side length, then:

[tex]\textsf{Area of one face of the smaller cube} = 12^2= 144\; \sf cm^2[/tex]

[tex]\textsf{Area of one face of the larger cube} =15^2 = 225 \; \sf cm^2[/tex]

So, the total surface area can be calculated as follows:

[tex]\textsf{Total surface area}=(5 \times 144) + (5 \times 225)+(225-144)\\\\\textsf{Total surface area}=720 + 1125+81\\\\\textsf{Total surface area}=1926\; \sf cm^2[/tex]

Therefore, the total surface area of the given figure is:

[tex]\Large\boxed{\boxed{1926\; \sf cm^2}}[/tex]