WHAT YOU NEED: ruler, scissors, pencil, piece of card. Image caption, STEP 1: Use the ruler and pencil to draw a diagonal line from the bottom left corner of the card to any point on the top edge of ...

The base and perpendicular height are at right angles. Showing that a parallelogram has the same area as a rectangle: Split the parallelogram into a right-angled triangle and a trapezium. Move the ...

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