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This pdf discusses finding the surface area of triangular prisms and cylinders step by step to get through the basics with examples.

1.
18. Tuesday 16th June: Surface area of triangular

prisms and cylinders

8X1 – Summer Term 2

Today’s lesson is about calculating the surface area of rectilinear shapes. I have

split the lesson into two parts:

Part 1: Surface area of triangular prisms

Part 2: Surface area of cylinders

Homework: 1 task on mathswatch

Answers are at the end of the document.

Part 1 – Surface area of triangular prisms

Surface area of a triangular prism:

EG 1: Find the surface area of a triangular prism

prisms and cylinders

8X1 – Summer Term 2

Today’s lesson is about calculating the surface area of rectilinear shapes. I have

split the lesson into two parts:

Part 1: Surface area of triangular prisms

Part 2: Surface area of cylinders

Homework: 1 task on mathswatch

Answers are at the end of the document.

Part 1 – Surface area of triangular prisms

Surface area of a triangular prism:

EG 1: Find the surface area of a triangular prism

2.
Find the surface area of each of the following trianglular prisms

3.
Part 2 – Surface area of cylinders

Two videos to watch to help understanding:

Surface area of cylinders:

EG 2: Find the surface area of the cylinder

Surface Area

Area of top: 𝝅 × 𝟑𝟐 = 𝟗𝝅

Area of base: 𝟗𝝅

Area of curved surface area: circumference of

the circle × height: 𝟔 × 𝝅 × 𝟏𝟎 = 𝟔𝟎𝝅

Total = 𝟔𝟎𝝅 + 𝟗 𝝅 + 𝟗𝝅 = 𝟕𝟖𝝅

EG 3: Working backwards, given the surface area

𝜋 × 32 + 𝜋 × 32 + (2 × 3 × 𝜋 × ℎ) = 84𝜋

18𝜋 + 6𝜋ℎ = 84𝜋

6𝜋ℎ = 66𝜋

6ℎ = 66

ℎ = 11

Two videos to watch to help understanding:

Surface area of cylinders:

EG 2: Find the surface area of the cylinder

Surface Area

Area of top: 𝝅 × 𝟑𝟐 = 𝟗𝝅

Area of base: 𝟗𝝅

Area of curved surface area: circumference of

the circle × height: 𝟔 × 𝝅 × 𝟏𝟎 = 𝟔𝟎𝝅

Total = 𝟔𝟎𝝅 + 𝟗 𝝅 + 𝟗𝝅 = 𝟕𝟖𝝅

EG 3: Working backwards, given the surface area

𝜋 × 32 + 𝜋 × 32 + (2 × 3 × 𝜋 × ℎ) = 84𝜋

18𝜋 + 6𝜋ℎ = 84𝜋

6𝜋ℎ = 66𝜋

6ℎ = 66

ℎ = 11

4.
Question 1 Question 2

Calculate the surface area to 2dp Calculate the surface area to 2dp

Question 3 Question 4

Calculate the surface area to 2dp Calculate the surface area in terms of 𝜋

Question 5 Question 6

Calculate the surface area in terms of 𝜋 Calculate the height

Question 7 Question 8

Calculate the height Calculate the height to 2 dp

Now complete the mathswatch

Calculate the surface area to 2dp Calculate the surface area to 2dp

Question 3 Question 4

Calculate the surface area to 2dp Calculate the surface area in terms of 𝜋

Question 5 Question 6

Calculate the surface area in terms of 𝜋 Calculate the height

Question 7 Question 8

Calculate the height Calculate the height to 2 dp

Now complete the mathswatch

5.
Answers – Part 1

1) 330cm²

2) 456cm²

3) 528cm²

4) 84cm²

5) 240cm²

6) 660cm²

Part 2

1) 1011.59cm²

2) 653.45cm²

3) 32.99m²

4) 28𝛑 cm²

5) 72𝛑 cm²

6) 35cm

7) 3cm

8) 1.3cm (1.30cm)

1) 330cm²

2) 456cm²

3) 528cm²

4) 84cm²

5) 240cm²

6) 660cm²

Part 2

1) 1011.59cm²

2) 653.45cm²

3) 32.99m²

4) 28𝛑 cm²

5) 72𝛑 cm²

6) 35cm

7) 3cm

8) 1.3cm (1.30cm)