Angles - points, lines and parallel lines

  • Flight Path
    problem

    Flight path

    Age
    16 to 18
    Challenge level
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    Use simple trigonometry to calculate the distance along the flight path from London to Sydney.
  • Overlapping Squares
    problem

    Overlapping squares

    Age
    7 to 11
    Challenge level
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    Have a good look at these images. Can you describe what is happening? There are plenty more images like this on NRICH's Exploring Squares CD.
  • Spirostars
    problem

    Spirostars

    Age
    16 to 18
    Challenge level
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    A spiropath is a sequence of connected line segments end to end taking different directions. The same spiropath is iterated. When does it cycle and when does it go on indefinitely?
  • Robo-Turn
    problem

    Robo-turn

    Age
    11 to 14
    Challenge level
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    Weekly Problem 16 - 2007
    Can you figure out how far the robot has travelled by the time it is first facing due East?
  • Semi-regular Tessellations
    problem

    Semi-regular tessellations

    Age
    11 to 16
    Challenge level
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    Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?

  • Orbiting Billiard Balls
    problem

    Orbiting billiard balls

    Age
    14 to 16
    Challenge level
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    What angle is needed for a ball to do a circuit of the billiard table and then pass through its original position?
  • Three Tears
    problem

    Three tears

    Age
    14 to 16
    Challenge level
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    Construct this design using only compasses
  • Dotty Relationship
    problem

    Dotty relationship

    Age
    7 to 11
    Challenge level
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    Can you draw perpendicular lines without using a protractor? Investigate how this is possible.
  • Pegboard Quads
    problem

    Pegboard quads

    Age
    14 to 16
    Challenge level
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    Make different quadrilaterals on a nine-point pegboard, and work out their angles. What do you notice?