Everything Maths Grade 10

VISIT:

This video explains how we can unfold solids into nets.

See video:2GS2atwww.everythingmaths.co.za

Worked example 2: Finding the surface area of a rectangular prism

QUESTION

Find the surface area of the following rectangular prism:

10 cm

2 cm

5 cm

SOLUTION

Step 1: Sketch and label the net of the prism

2 cm

5 cm

2 cm 5 cm

10 cm

Step 2: Find the areas of the different shapes in the net

large rectangle=perimeter of small rectanglelength

= (2 + 5 + 2 + 5) 10

= 14 10

=140 cm^2

2 small rectangle= 2 (52)

= 2 (10)

=20 cm^2

Step 3: Find the sum of the areas of the faces

large rectangle+ 2small rectangle= 140 + 20 = 160

Step 4: Write the final answer
The surface area of the rectangular prism is 160 cm^2.

422 13.2. Right prisms and cylinders