Perimeter of a Triangle

Perimeter of shapes and Area of a Triangle

How do you find the Perimeter?

To find the perimeter, add the length of ALL sides.

6 + 6 + 6 + 6 = ?

The perimeter of this shape is 24.

24 what?

If you walked all the way around this shape you would walk 24 feet.

Multiple Choice

What is the perimeter formula for a triangle?

• P=4s

• P= a+b+c

• P=2l+2w

Perimeter Formulas

Triangles:

Perimeter: P = a + b + c

Who cares?

If you were building a fence around the outside of your yard, you would need to know the Perimeter

Multiple Choice

What is the perimeter?

• 124.6m

• 117.8m

• 135.4m

• 126.6m

Multiple Choice

The perimeter of the figure below is 80.9 ft. Find the length of the missing side.

• 9.3 ft

• 5.4 ft

• 4.3 ft

• 3.6 ft

Area of Triangles

Area formula A= ½ × base × height or Area = b x h divided by 2   Find the base & height by finding where the right angle is!!

Multiple Choice

What is the area, in square inches, of the shape below?

• 84.48 in2

• 42.24 in2

• 63.36in2

• 56.32in2

Multiple Choice

The area of the triangle below is 38.28 square meters. What is the length of the base?

• 8.8m

• 4.35m

• 19.14m

• 7.2m

Fill in the Blanks

Work on Delta

*Area of Triangles  

*Perimeter (numerical)