Three buoys AAA, BBB, and C C\,C form a triangle. The distance AB=20AB = 20AB=20 nautical miles (nm), BC=25 nmBC = 25\text{ nm}BC=25 nm, and AC=35 nmAC = 35\text{ nm}AC=35 nm.
Work out the size of angle ABCABCABC.
Give your answer to the nearest degree.
The Cosine Rule Questions
Practise OCR GCSE Maths The Cosine Rule with exam-style questions for Foundation and Higher tier. 44 questions, matched to the OCR GCSE Maths (J560) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.