| Angle Type | Position | Relationship | Memory Trick |
|---|---|---|---|
| Corresponding | Same position at each intersection | EQUAL (make F shape) | F for "Fidentical" |
| Alternate | Opposite sides, between parallel lines | EQUAL (make Z shape) | Z for "Zee same" |
| Co-interior | Same side, between parallel lines | ADD to 180° (make C shape) | C for "C them add up" |
Also called: Co-interior angles = Allied angles = Interior angles
This key facts covers The Three Key Rules 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 2 of 9 in this topic. Use this key facts 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?
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.