Which Statements Are True About A Rectangular Pyramid With A Height Of 15 Inches And A Base With Dimensions Of 12 Inches By 9 Inches? Select Three Options.A. The Area Of The Base Of The Pyramid, B B B , Is 36 In 2 36 \, \text{in}^2 36 In 2 .B. The Area

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Introduction

A rectangular pyramid is a three-dimensional shape with a rectangular base and four triangular faces that meet at the apex. In this article, we will analyze a specific rectangular pyramid with a height of 15 inches and a base with dimensions of 12 inches by 9 inches. We will examine three statements about this pyramid and determine which ones are true.

Calculating the Area of the Base

The area of the base of the pyramid, denoted by BB, can be calculated using the formula for the area of a rectangle:

B=lengthΓ—widthB = \text{length} \times \text{width}

In this case, the length of the base is 12 inches and the width is 9 inches. Therefore, the area of the base is:

B=12Γ—9=108 in2B = 12 \times 9 = 108 \, \text{in}^2

This means that statement A, which claims that the area of the base of the pyramid is 36 in236 \, \text{in}^2, is false.

Calculating the Volume of the Pyramid

The volume of a rectangular pyramid can be calculated using the formula:

V=13BhV = \frac{1}{3}Bh

where BB is the area of the base and hh is the height of the pyramid. In this case, the area of the base is 108 in^2 and the height is 15 inches. Therefore, the volume of the pyramid is:

V=13Γ—108Γ—15=540 in3V = \frac{1}{3} \times 108 \times 15 = 540 \, \text{in}^3

Calculating the Surface Area of the Pyramid

The surface area of a rectangular pyramid can be calculated by adding the areas of the four triangular faces and the base. The area of each triangular face is given by:

A=12Γ—baseΓ—heightA = \frac{1}{2} \times \text{base} \times \text{height}

In this case, the base of each triangular face is 12 inches and the height is 15 inches. Therefore, the area of each triangular face is:

A=12Γ—12Γ—15=90 in2A = \frac{1}{2} \times 12 \times 15 = 90 \, \text{in}^2

Since there are four triangular faces, the total area of the triangular faces is:

Atriangular=4Γ—90=360 in2A_{\text{triangular}} = 4 \times 90 = 360 \, \text{in}^2

The area of the base is 108 in^2. Therefore, the total surface area of the pyramid is:

Atotal=Atriangular+B=360+108=468 in2A_{\text{total}} = A_{\text{triangular}} + B = 360 + 108 = 468 \, \text{in}^2

Evaluating the Statements

Based on our calculations, we can evaluate the three statements about the rectangular pyramid:

  • Statement A: The area of the base of the pyramid is 36 in236 \, \text{in}^2. False
  • Statement B: The area of the base of the pyramid is 108 in2108 \, \text{in}^2. True
  • Statement C: The surface area of the pyramid is 468 in2468 \, \text{in}^2. True

Conclusion

In this article, we analyzed a rectangular pyramid with a height of 15 inches and a base with dimensions of 12 inches by 9 inches. We calculated the area of the base, the volume of the pyramid, and the surface area of the pyramid. Based on our calculations, we determined that statement A is false, statement B is true, and statement C is true.

Key Takeaways

  • The area of the base of a rectangular pyramid can be calculated using the formula: B=lengthΓ—widthB = \text{length} \times \text{width}.
  • The volume of a rectangular pyramid can be calculated using the formula: V=13BhV = \frac{1}{3}Bh.
  • The surface area of a rectangular pyramid can be calculated by adding the areas of the four triangular faces and the base.

Further Reading

For more information on rectangular pyramids, including their properties and applications, see the following resources:

References

Glossary

  • Base: The rectangular face of the pyramid that is in contact with the ground.
  • Height: The vertical distance from the base of the pyramid to the apex.
  • Apex: The point at the top of the pyramid.
  • Triangular face: One of the four triangular faces that meet at the apex.
  • Surface area: The total area of the pyramid, including the base and the four triangular faces.

Introduction

Rectangular pyramids are a fundamental concept in geometry, and they have many practical applications in various fields such as architecture, engineering, and design. In this article, we will answer some of the most frequently asked questions about rectangular pyramids.

Q: What is a rectangular pyramid?

A: A rectangular pyramid is a three-dimensional shape with a rectangular base and four triangular faces that meet at the apex. It is a type of pyramid that has a rectangular base, as opposed to a square or triangular base.

Q: What are the key properties of a rectangular pyramid?

A: The key properties of a rectangular pyramid include:

  • Base: The rectangular face of the pyramid that is in contact with the ground.
  • Height: The vertical distance from the base of the pyramid to the apex.
  • Apex: The point at the top of the pyramid.
  • Triangular face: One of the four triangular faces that meet at the apex.
  • Surface area: The total area of the pyramid, including the base and the four triangular faces.

Q: How do you calculate the area of the base of a rectangular pyramid?

A: The area of the base of a rectangular pyramid can be calculated using the formula:

B=lengthΓ—widthB = \text{length} \times \text{width}

For example, if the length of the base is 12 inches and the width is 9 inches, the area of the base would be:

B=12Γ—9=108 in2B = 12 \times 9 = 108 \, \text{in}^2

Q: How do you calculate the volume of a rectangular pyramid?

A: The volume of a rectangular pyramid can be calculated using the formula:

V=13BhV = \frac{1}{3}Bh

where BB is the area of the base and hh is the height of the pyramid. For example, if the area of the base is 108 in^2 and the height is 15 inches, the volume of the pyramid would be:

V=13Γ—108Γ—15=540 in3V = \frac{1}{3} \times 108 \times 15 = 540 \, \text{in}^3

Q: How do you calculate the surface area of a rectangular pyramid?

A: The surface area of a rectangular pyramid can be calculated by adding the areas of the four triangular faces and the base. The area of each triangular face is given by:

A=12Γ—baseΓ—heightA = \frac{1}{2} \times \text{base} \times \text{height}

For example, if the base of each triangular face is 12 inches and the height is 15 inches, the area of each triangular face would be:

A=12Γ—12Γ—15=90 in2A = \frac{1}{2} \times 12 \times 15 = 90 \, \text{in}^2

Since there are four triangular faces, the total area of the triangular faces would be:

Atriangular=4Γ—90=360 in2A_{\text{triangular}} = 4 \times 90 = 360 \, \text{in}^2

The area of the base is 108 in^2. Therefore, the total surface area of the pyramid would be:

Atotal=Atriangular+B=360+108=468 in2A_{\text{total}} = A_{\text{triangular}} + B = 360 + 108 = 468 \, \text{in}^2

Q: What are some real-world applications of rectangular pyramids?

A: Rectangular pyramids have many practical applications in various fields such as architecture, engineering, and design. Some examples include:

  • Building design: Rectangular pyramids are often used in building design to create unique and visually appealing structures.
  • Engineering: Rectangular pyramids are used in engineering to create structures that can withstand various types of stress and load.
  • Design: Rectangular pyramids are used in design to create unique and visually appealing shapes and forms.

Q: What are some common mistakes to avoid when working with rectangular pyramids?

A: Some common mistakes to avoid when working with rectangular pyramids include:

  • Incorrect calculations: Make sure to double-check your calculations to ensure that you are getting the correct results.
  • Incorrect measurements: Make sure to take accurate measurements to ensure that your pyramid is the correct size and shape.
  • Incorrect construction: Make sure to follow proper construction techniques to ensure that your pyramid is stable and secure.

Conclusion

In this article, we have answered some of the most frequently asked questions about rectangular pyramids. We have covered topics such as the key properties of a rectangular pyramid, how to calculate the area of the base, how to calculate the volume, and how to calculate the surface area. We have also discussed some real-world applications of rectangular pyramids and some common mistakes to avoid when working with them.

Key Takeaways

  • The key properties of a rectangular pyramid include the base, height, apex, triangular face, and surface area.
  • The area of the base of a rectangular pyramid can be calculated using the formula: B=lengthΓ—widthB = \text{length} \times \text{width}.
  • The volume of a rectangular pyramid can be calculated using the formula: V=13BhV = \frac{1}{3}Bh.
  • The surface area of a rectangular pyramid can be calculated by adding the areas of the four triangular faces and the base.
  • Rectangular pyramids have many practical applications in various fields such as architecture, engineering, and design.

Further Reading

For more information on rectangular pyramids, including their properties and applications, see the following resources:

References

Glossary

  • Base: The rectangular face of the pyramid that is in contact with the ground.
  • Height: The vertical distance from the base of the pyramid to the apex.
  • Apex: The point at the top of the pyramid.
  • Triangular face: One of the four triangular faces that meet at the apex.
  • Surface area: The total area of the pyramid, including the base and the four triangular faces.