Compound Shapes
Ages 10–14Difficulty adapts to you
Compound Shapes
Compound shapes are made by joining two or more simple shapes together. To find the total area, split the shape into parts, find each area, then add them up.
Your goals
- ✓You can find the area of shapes made by combining simple shapes.
- ✓You can use compound shape, overlap correctly.
- ✓You can make sure your parts cover the shape once, with no gaps or overlaps.
Words to know
- compound shape:
- A shape made from two or more simpler shapes.
- overlap:
- A region counted by more than one part.
Examples
- 1An L-shape can be split into two rectangles. Find each area and add.
- 2A house shape = rectangle (wall) + triangle (roof). Add both areas.
More than one way to solve it
Try each method, then choose the one you can explain and check most clearly.
Method 1
Split and add
- 1.Divide the shape into familiar pieces.
- 2.Find each area.
- 3.Add the areas.
Example: Split an L-shape into two rectangles and add their areas.
Method 2
Complete and subtract
- 1.Complete the outer rectangle.
- 2.Find the missing area.
- 3.Subtract it from the whole.
Example: Outer area 60 cm² minus a 12 cm² cut-out gives 48 cm².
Check these
- • Do not count an overlapping region twice.
- • Keep every number, symbol, label, and unit in its correct place.
- • Choose the method that makes each step easiest to explain and check.
Helpful habits
- • Read the whole question before choosing what to do.
- • Show one clear step at a time and check each step.
- • If you are stuck, draw a model, try smaller numbers, or revisit the example.
Now try your own
Create your own compound shapes example, solve it, and explain how you checked it.
Spark
Creativity & Innovation“Maths is everywhere — in music, art, and nature!”