GCSE · Angles & polygons

Angle rules & giving reasonsExam-style questions

Why angles at a point make 360°, angles on a straight line make 180°, and vertically opposite angles are equal; the triangle and quadrilateral angle sums; isosceles triangles; and how to write the reasons examiners insist on.

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12 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    The diagram shows a quadrilateral.(2x − 10)°(4x + 15)°(x + 50)°(3x + 5)°Diagram NOT accurately drawn

    (a) Work out the size of the smallest angle of the quadrilateral.

    (b) Explain how you can check that your four angles are correct.
    Level 4 · 5 marksTry it
  2. 2
    The diagram shows a quadrilateral.x°85°95°2x°Diagram NOT accurately drawn

    Work out the value of xx. Give a reason for your answer.
    Level 4 · 3 marksTry it