1. Starter Questions Q1. 12.5% of 360 Q2. Calculate 5 + 6 x 7
Q3. Solve for y
2( y – 5 ) = y + 3 1

2. To be able to find the surface area
Learning Intentions
To be able to find the surface area
of a triangular prism

3. Find the surface area of the right angle prism
Example
Find the surface area of the right angle prism
Working
Triangle Area =
= 2 x3 =6cm2
Rectangle 1 Area = l x b
= 3 x10 =30cm2
4cm
5cm
Rectangle 2 Area = l x b
3cm
10cm
= 4 x 10 =40cm2
Rectangle 3 Area = l x b
2 triangles the same
= 5 x 10 =50cm2
1 rectangle 3cm by 10cm
Total Area
= = 132cm2
1 rectangle 4cm by 10cm
1 rectangle 5cm by 10cm

4. Surface Areaof a Triangular Prism
Working
Triangle Area =
= 2 x4 = 8 cm2
5cm
Rectangle 1 Area = l x b
4cm
= 5 x10 =50cm2
10cm
Rectangle 2 Area = l x b
4cm
= 5 x10 =50cm2
2 triangles the same
Rectangle 3 Area = l x b
2 rectangle the same 5cm by 10cm
= 4 x 10 =40cm2
1 rectangle 4cm by 10cm
Total Area
= = 156cm2

5. Surface Area Triangular Prism
Now try Ex 7.1
Ch 2 Pg 33