Area of Triangles & Parallelograms

MathematicsMeasurementAges 10–11

Calculate the area of parallelograms and triangles using formulae (A = b × h for parallelograms, A = ½ × b × h for triangles)

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“If your child is cutting triangular pieces of cloth where the base is 8 cm and the height is 5 cm, can they use a formula to work out the area of each piece?”

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Activity. Calculate the area of parallelograms and triangles using formulae (A = b × h for parallelograms, A = ½ × b × h for triangles)

What to notice. Calculate the area of a parallelogram with base 8 cm and height 5 cm • Calculate the area of a triangle with base 12 cm and height 7 cm • Explain why the area of a triangle is half the area of a related parallelogram

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If your child is cutting triangular pieces of cloth where the base is 8 cm and the height is 5 cm, can they use a formula to work out the area of each piece?

Calculate the area of parallelograms and triangles using formulae (A = b × h for parallelograms, A = ½ × b × h for triangles)

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Calculate the area of a parallelogram with base 8 cm and height 5 cm
Calculate the area of a triangle with base 12 cm and height 7 cm
Explain why the area of a triangle is half the area of a related parallelogram