Area - triangles, quadrilaterals, compound shapes

  • Same Height
    problem

    Same height

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    A trapezium is divided into four triangles by its diagonals. Can you work out the area of the trapezium?
  • Isosceles
    problem

    Isosceles

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    Prove that a triangle with sides of length 5, 5 and 6 has the same area as a triangle with sides of length 5, 5 and 8. Find other pairs of non-congruent isosceles triangles which have equal areas.
  • Linkage
    problem

    Linkage

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    Four rods, two of length a and two of length b, are linked to form a kite. The linkage is moveable so that the angles change. What is the maximum area of the kite?
  • Square pizza
    problem

    Square pizza

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    Can you show that you can share a square pizza equally between two people by cutting it four times using vertical, horizontal and diagonal cuts through any point inside the square?
  • Disappearing square
    problem

    Disappearing square

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    Do you know how to find the area of a triangle? You can count the squares. What happens if we turn the triangle on end? Press the button and see. Try counting the number of units in the triangle now. Do you have any interesting findings to report?
  • Rati-o
    problem

    Rati-o

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    Points P, Q, R and S each divide the sides AB, BC, CD and DA respectively in the ratio of 2 : 1. Join the points. What is the area of the parallelogram PQRS in relation to the original rectangle?
  • Squ-areas
    problem

    Squ-areas

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    Three squares are drawn on the sides of a triangle ABC. Their areas are respectively 18 000, 20 000 and 26 000 square centimetres. If the outer vertices of the squares are joined, three more triangular areas are enclosed. What is the area of this convex hexagon?
  • Rod Area
    problem

    Rod area

    Age
    7 to 11

    This task challenges you to create symmetrical U shapes out of rods and find their areas.

  • Twice as Big?
    problem

    Twice as big?

    Age
    7 to 11
    Challenge level
    filled star empty star empty star

    Investigate how the four L-shapes fit together to make an enlarged L-shape. You could explore this idea with other shapes too.

  • Triangle Island
    problem

    Triangle island

    Age
    7 to 11
    Challenge level
    filled star filled star filled star
    You have pitched your tent (the red triangle) on an island. Can you move it to the position shown by the purple triangle making sure you obey the rules?