Surface Area Homework 3 Answer Key: A thorough look
Understanding surface area is a foundational skill in geometry, with applications in fields ranging from architecture to packaging design. Now, this article breaks down Surface Area Homework 3, providing step-by-step solutions, key formulas, and practical examples to help students master the concept. Whether you’re struggling with cubes, cylinders, or composite shapes, this guide will clarify the process and build confidence Simple, but easy to overlook..
What Is Surface Area?
Surface area refers to the total area covered by the outer surfaces of a 3D object. It is measured in square units (e.g., cm², m²). Calculating surface area is essential for tasks like determining the amount of material needed to cover an object or the paint required for a wall.
Key Formulas for Surface Area
Before diving into the homework problems, review these formulas:
- Cube: $ SA = 6s^2 $ (where $ s $ = side length)
- Rectangular Prism: $ SA = 2(lw + lh + wh) $ (where $ l $ = length, $ w $ = width, $ h $ = height)
- Cylinder: $ SA = 2\pi r(r + h) $ (where $ r $ = radius, $ h $ = height)
- Sphere: $ SA = 4\pi r^2 $ (where $ r $ = radius)
- Triangular Prism: $ SA = 2(\frac{1}{2}bh) + ph $ (where $ b $ = base, $ h $ = height of triangle, $ p $ = perimeter of base, $ h $ = prism height)
Surface Area Homework 3: Step-by-Step Solutions
Problem 1: Cube
Question: A cube has a side length of 5 meters. What is its surface area?
Solution:
- Use the formula $ SA = 6s^2 $.
- Plug in $ s = 5 $:
$ SA = 6 \times (5)^2 = 6 \times 25 = 150 , \text{m}^2 $.
Answer: 150 square meters.
Problem 2: Rectangular Prism
Question: A rectangular box has dimensions 3 cm (length), 4 cm (width), and 6 cm (height). Calculate its surface area.
Solution:
- Apply $ SA = 2(lw + lh + wh) $.
- Compute each term:
- $ lw = 3 \times 4