Angles in polygons

  • Plaid patterned bow tie.
    problem

    Bow Tie

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Show how this pentagonal tile can be used to tile the plane and describe the transformations which map this pentagon to its images in the tiling.

  • Nonagon Angle
    problem

    Nonagon Angle

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 53 - 2012
    ABCDEFGHI is a regular nine-sided polygon (called a 'nonagon' or 'enneagon'). What is the size of the angle FAE ?

  • Integral Polygons
    problem

    Integral Polygons

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Each interior angle of a particular polygon is an obtuse angle which is a whole number of degrees. What is the greatest number of sides the polygon could have?

  • Dodecagon Angles
    problem

    Dodecagon Angles

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 50 - 2012
    The diagram shows a regular dodecagon. What is the size of the marked angle?

  • Hexapentagon
    problem

    Hexapentagon

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 53 - 2007
    The diagram shows a regular pentagon and regular hexagon which overlap. What is the value of x?

  • U in a Pentagon
    problem

    U in a Pentagon

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 18 - 2008
    The diagram shows a regular pentagon. Can you work out the size of the marked angle?

  • Right Angled Octagon
    problem

    Right Angled Octagon

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 38 - 2008
    A quadrilateral can have four right angles. What is the largest number of right angles an octagon can have?

  • Triangle Split
    problem

    Triangle Split

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    Weekly Problem 50 - 2008
    The lengths SP, SQ and SR are equal and the angle SRQ is x degrees. What is the size of angle PQR?

  • Square Triangle
    problem

    Square Triangle

    Age
    11 to 14
    Challenge level
    filled star filled star empty star

    How many triangles have all three angles perfect squares (in degrees)?

  • Getting an angle
    problem

    Getting an Angle

    Age
    11 to 14
    Challenge level
    filled star filled star filled star

    How can you make an angle of 60 degrees by folding a sheet of paper twice?