Junior Cycle · Area, Volume and Measurement ⏱ Tested in 1 exam question since 2024 Lesson 3 of 7

JCHL AVM 3: Triangles, Parallelograms and Trapeziums

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You’ll learn

  • Triangle: area = ½ × base × perpendicular height
  • Parallelogram: area = base × perpendicular height (a triangle is half a parallelogram)
  • Trapezium: area = ((a+b)/2) × h — average the two parallel sides, then × height

Formula used

Triangle: A = ½ah

Parallelogram: A = ah

Trapezium: A = ((a+b)/2)h

On page 9 of the log tables — read it off, don’t memorise.

Most recent exam questions

  • 2024 Q13(c)(ii)

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