GCSE · Circles, arcs & sectors

Circle theoremsExam-style questions

The theorems about angles in a circle — at the centre, in a semicircle, in the same segment, and in a cyclic quadrilateral — why each is true, and the exact wording examiners require as a reason.

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

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    PP, QQ and RR are points on a circle, centre OO.

    SPTSPT is the tangent to the circle at PP.67°49°OPQRTSAngle TPQ=67°TPQ = 67°

    Angle RPS=49°RPS = 49°

    Work out the size of angle OQROQR.

    Write down any circle theorems that you use.

    (4 marks)
    Level 5 · 4 marksTry it
  2. 2
    AA, BB and CC are points on a circle with centre OO.

    Angle ACB=58°ACB = 58°.58°xABCODiagram NOT accurately drawn

    Work out the size of the angle marked xx (angle OABOAB). You must give reasons for each stage of your working.
    Level 5 · 4 marksTry it
  3. 3
    AA, BB, CC and DD are points on a circle. The chords ACAC and BDBD cross at the point EE.

    Angle ADB=40°ADB = 40° and angle DBC=33°DBC = 33°.40°x33°ABCDEDiagram NOT accurately drawn

    (a) Write down the size of angle ACBACB. Give a reason for your answer.

    (b) Work out the size of angle AEBAEB, marked xx.
    Level 5 · 4 marksTry it