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. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 2 of 8 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 2 of 8
Practice
12 questions
Recall
3 flashcards
The Three Key Rules
| 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