Question P4 Rectangle and square measurement
A square has area 81 cm². Find its side length.
Answer
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Rectangle and square measurement
Use opposite equal sides, undo the area or perimeter formula, and count each outside edge once.
In this one. The side is the positive number that multiplied by itself gives the square’s area.
Squares tiling a rectangle, or a shape made of several rectangles joined together, point here. The question asks for area, perimeter, or the length of a missing side.
Children multiply length by width when the question actually asks for perimeter. On a composite shape, they add only the labelled sides and miss the ones they must work out themselves.
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