A triangular sail DEF DEF\,DEF has side DE=8.4DE = 8.4DE=8.4 m and side DF=11.2DF = 11.2DF=11.2 m. The area of the sail is 35 m2.
Calculate the perimeter of the sail DEFDEFDEF.
Give your answer to 3 significant figures.
Practise AQA GCSE Maths The Cosine Rule with exam-style questions for Foundation and Higher tier. 44 questions, matched to the AQA GCSE Maths (8300) specification and written in Paper 1, Paper 2 and Paper 3 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.