Worked Example 2: Alternate Angles

Part of Angles in Parallel Lines · Section 5 of 9

Study NotesUnit: Geometry & MeasuresGCSE

Find angle x if the alternate angle is 118°.

Step 1 Recall the rule for alternate angles

Alternate angles make a Z-shape

Alternate angles are EQUAL

Step 2 Find x

x = 118°

Reason: Alternate angles on parallel lines

This study notes covers Worked Example 2: Alternate Angles within Angles in Parallel Lines for GCSE Mathematics. Revise Angles in Parallel Lines in Geometry & Measures for GCSE Mathematics with 12 exam-style questions and 3 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 5 of 9 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.

Practice questions for Angles in Parallel Lines

Two parallel lines are cut by a transversal. Which statement about alternate angles is correct?

  • A. Alternate angles add up to 180°
  • B. Alternate angles are equal
  • C. Alternate angles add up to 90°
  • D. Alternate angles are supplementary
1 markfoundation

State the THREE angle rules that apply when a transversal crosses two parallel lines. For each rule, state whether the angles are equal or supplementary.

2 marksstandard

Quick recall flashcards

Alternate Angles
Z-shape on parallel lines, equal
Co-interior Angles
C-shape on parallel lines, add to 180°

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