Understanding Perimeter of Triangles

In this video, Mr. Jay explains how to find the perimeter of a triangle. He begins by defining perimeter as the distance around the outside of a shape. The video includes two examples: one with a regular triangle and another with a right triangle. In each example, Mr. Jay demonstrates how to calculate the perimeter by adding the lengths of all sides. He emphasizes that the order of addition does not affect the result. The video concludes with a recap of the key concept that perimeter is the sum of all side lengths.

What is the perimeter of a shape?

• The diagonal length of a shape

• The area inside a shape

• The volume of a shape

• The distance around the outside of a shape

Tags

CCSS.3.MD.D.8

How do you find the perimeter of a triangle?

• Divide the lengths of all sides

• Add the lengths of all sides

• Subtract the lengths of all sides

• Multiply the lengths of all sides

Tags

CCSS.3.MD.D.8

What is the perimeter of a triangle with sides 6m, 13m, and 10m?

• 29 meters

• 31 meters

• 30 meters

• 26 meters

In Example 1, what is the sum of the first two sides of the triangle?

• 20 meters

• 19 meters

• 18 meters

• 16 meters

Tags

CCSS.3.MD.D.8

What is the perimeter of a right triangle with sides 25 inches, 24 inches, and 7 inches?

• 54 inches

• 56 inches

• 55 inches

• 57 inches

In Example 2, what is the sum of the first two sides of the triangle?

• 49 inches

• 48 inches

• 51 inches

• 50 inches

Tags

CCSS.3.MD.D.8

What is the key takeaway about finding the perimeter of a triangle?

• Multiply the longest side by three

• Add all the side lengths together

• Subtract the smallest side from the largest

• Divide the total length by the number of sides

Why is it important to know the perimeter of a shape?

• To calculate the area

• To understand the shape's volume

• To find the shape's diagonal

• To determine the distance around the shape

Tags

CCSS.3.MD.D.8

What should you remember about the order of adding side lengths?

• Always add the shortest side first

• Always add the longest side first

• The order does not matter

• The order affects the perimeter

Tags

CCSS.3.MD.D.8