GCSE · Angles & polygons

Angles in parallel linesExam-style questions

Why corresponding angles are equal, why alternate angles are equal, and why co-interior angles add up to 180° — plus the exact naming examiners accept, and the add-a-parallel-line trick for awkward figures.

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

DifficultyAllLevel 1Level 2Level 3Level 4Level 5
  1. 1
    The diagram shows two parallel lines and a straight line crossing them.(2x + 30)°(3x − 10)°Diagram NOT accurately drawn

    Work out the value of xx. (3 marks)
    Level 3 · 3 marksTry it
  2. 2
    The line AFBAFB is parallel to the line CHGDCHGD.

    EFGEFG is a straight line.104°52°ABCDEFGHShow that triangle FGHFGH is isosceles.

    Give a reason for each stage of your working.

    (5 marks)
    Level 3 · 5 marksTry it
  3. 3
    The diagram shows quadrilateral PQRSPQRS.4x − 53x + 105x − 203xPQRSThe angles marked on the diagram are in degrees.

    Show that PQRSPQRS is a trapezium.

    (4 marks)
    Level 3 · 4 marksTry it
  4. 4
    The diagram shows two parallel lines crossed by a straight line.118°y°z°Diagram NOT accurately drawn

    (a) Work out the size of the angle marked yy. Give a reason for your answer.

    (b) Write down the size of the angle marked zz. Give a reason for your answer.
    Level 3 · 4 marksTry it
  5. 5
    The diagram shows two parallel lines crossed by a straight line.71°y°z°Diagram NOT accurately drawn

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

    (b) Work out the size of the angle marked zz. Give a reason for your answer.
    Level 3 · 4 marksTry it