Area of irregular shapes, step by step
Not every shape can be counted in one clean sweep, and that is exactly where organizing a count becomes a skill.
The question
squares
Area of an L-shape by counting
an L, not a rectangle
whole:8 × 6 =48
bite:4 × 1 =4
48 − 4 =44
first way:48 − 4 =44
strip:8 × 5 =40
upright:4 × 1 =4
40 + 4 =44 squares
- There is no single row that runs all the way across this one, so counting rows does not work as it stands. Cut it into pieces that ARE rectangles — and there is more than one way.
- First way: count the whole rectangle it would be — 8 × 6 = 48 — then take off the bite, 4 × 1 = 4. That leaves 44.
- Second way: two rectangles. The strip underneath is 8 × 5 = 40, the part standing on it is 4 × 1 = 4, and 40 + 4 = 44. Two ways agreeing is how you know a count is right.
How it works.
- 01
There is no single row that runs all the way across this one, so counting rows does not work as it stands. Cut it into pieces that ARE rectangles — and there is more than one way.
- 02
First way: count the whole rectangle it would be — 8 × 6 = 48 — then take off the bite, 4 × 1 = 4. That leaves 44.
- 03
Second way: two rectangles. The strip underneath is 8 × 5 = 40, the part standing on it is 4 × 1 = 4, and 40 + 4 = 44. Two ways agreeing is how you know a count is right.