How do you find the surface area of 3D shapes?

Calculating the surface area of 3D shapes is an important skill in geometry and can be used in many practical applications. The surface area is the sum of the areas of all the faces (or surfaces) of a 3D shape. The formula for finding the surface area of each shape varies, but here are some common 3D shapes and their corresponding formulas:

• Cube: Surface area = 6a² (where a is the length of one side)
• Rectangular Prism: Surface area = 2lw + 2lh + 2wh (where l, w, and h are the length, width, and height respectively)
• Cylinder: Surface area = 2πr² + 2πrh (where r is the radius of the base and h is the height)
• Sphere: Surface area = 4πr² (where r is the radius)

It's important to remember that the units of measurement used for the length, width, and height (or radius) must be consistent when calculating surface area. Once you have calculated the surface area of a 3D shape, you can use this measurement to calculate other properties, such as the volume or density.

Practice is key when it comes to mastering the skill of calculating surface area. There are many online resources and practice problems available for free to help you improve your skills.