Understanding Surface Area of a Triangular Pyramid

The video tutorial by Mr. J explains how to find the surface area of a triangular pyramid. It covers the calculation of the base area using the formula for the area of a triangle and the lateral area by finding the area of the triangular faces. The tutorial demonstrates adding these areas to get the total surface area. An alternative method using a specific formula for regular triangular pyramids is also presented, which condenses the calculation of the lateral area into a single step.

What is the total number of faces in a triangular pyramid?

• Three

• Six

• Five

• Four

Which formula is used to calculate the area of a triangle?

• Base times height

• Base divided by height

• One-half times base times height

• Base plus height

If the base of a triangular face is 5 cm and the height is 9 cm, what is the area of the face?

• 30 square cm

• 10 square cm

• 45 square cm

• 22.5 square cm

How do you find the total surface area of a triangular pyramid?

• Add the areas of the base and lateral faces

• Multiply the areas of the base and lateral faces

• Divide the area of the base by the lateral faces

• Subtract the area of the base from the lateral faces

What is the purpose of using the alternative formula for regular triangular pyramids?

• To calculate the height of the pyramid

• To find the volume of the pyramid

• To condense the calculation of all lateral faces into one formula

• To simplify the calculation of the base area

What is the slant height used for in the alternative formula?

• To calculate the base area

• To find the height of the pyramid

• To determine the lateral area

• To measure the perimeter

In a regular triangular pyramid, what must be true about the base?

• All sides are the same

• All sides are different

• The base is a square

• Two sides are equal

What is the perimeter of a triangular base with sides of 5 cm each?

• 15 cm

• 10 cm

• 25 cm

• 20 cm

How does the alternative formula for surface area differ from the basic method?

• It only works for non-regular pyramids

• It ignores the base area

• It combines the lateral areas into one calculation

• It uses the volume instead of area

What is the total surface area of the triangular pyramid in the example?

• 67.5 square cm

• 78.33 square cm

• 22.5 square cm

• 45 square cm