4MA1/1FR Jan 2019, Question 21: Angles in a Triangle
Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 1FR (Foundation) · Calculator · 4 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Triangle PQR has equal sides RP and RQ, with angles P = 3x + 10, Q = x + 52 and R = y, all in degrees. Find y, showing algebraic working.
Summarised in our own words. Use the official paper for the exact wording and the diagram.
Solution · 4 marks
- 1RP = RQ, so angle P = angle Q: 3x + 10 = x + 52
- 22x = 42, so x = 21
- 3Angle P = 3 × 21 + 10 = 73° and angle Q = 21 + 52 = 73°
- 4Angles in a triangle add to 180°: y = 180 − 73 − 73 = 34
Answer34
Stuck on a step? Read the free lesson: Angles in a Triangle
Practise more angles in a triangle questions
Real 4MA1 past-paper questions, marked on your working like the exam, with a worked solution for every part.
Practise free on LemmaraMore past-paper questions on angles in a triangle
Also searched as: 4MA1 1FR January 2019 · 4MA1/1FR · 4ma1 jan19 1fr · question 21.
Lemmara is an independent study tool, not affiliated with or endorsed by Pearson Edexcel. The worked solutions are Lemmara’s own.