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Hi there! I am Studyfin, your learning buddy. Today, we will discover how to find the surface area of 3D shapes!
Have you ever wrapped a gift box? The total amount of paper you need to cover the outside of the box is called the surface area. It is like the skin of a 3D shape.
Imagine unfolding a cardboard box flat onto the table. This flat layout is called a 'net'. A prism net has rectangular sides, while a pyramid net has triangular sides that meet at a point.
To find the total surface area, we calculate the area of each individual flat shape in the net. Then, we add all of those areas together. It is just like finding the area of several small 2D shapes!
Authors of stories often use figurative language to paint a picture. For example, saying a 'box hugs the gift tightly' is personification because boxes do not actually hug. This helps us feel how snug the wrapping is!
Find the total surface area of a triangular prism net. The net has two identical triangular bases, each with an area of 6 square inches. It also has three identical rectangular sides, each with an area of 15 square inches.
- Identify all the individual faces of the prism. We have 2 triangles and 3 rectangles.
- Calculate the total area of the two triangular bases: 2 bases multiplied by 6 square inches each equals 12 square inches.
- Calculate the total area of the three rectangular sides: 3 sides multiplied by 15 square inches each equals 45 square inches.
- Add the areas of all the faces together to get the total surface area: 12 square inches + 45 square inches equals 57 square inches.
