Worked Example 3: Exterior Angle
Part of Properties of Triangles — GCSE Mathematics
This study notes covers Worked Example 3: Exterior Angle within Properties of Triangles for GCSE Mathematics. Revise Properties of Triangles 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 6 of 8 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 6 of 8
Practice
12 questions
Recall
3 flashcards
Worked Example 3: Exterior Angle
A triangle has interior angles of 55° and 72°. Find the exterior angle at the third vertex.
Step 1 Use the exterior angle theorem
Exterior angle = sum of opposite interior angles
Exterior = 55° + 72° = 127°