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
    ABCABC is a triangle with AB=ACAB = AC. BCDBCD is a straight line.

    Angle ACD=116°ACD = 116°.116°ABCDDiagram NOT accurately drawn

    Work out the size of angle BACBAC. Give a reason for each stage of your working.
    Level 5 · 4 marksTry it