A parallelogram ABCD ABCD\,ABCD has area 63 cm2. Given AB AB\,AB has length 7 cm, BC BC\,BC has length 10 cm and angle ABC ABC\,ABC is obtuse.
Find the size of angle ABC ABC\,ABC to 2 decimal places.
217 exam-style questions on Edexcel A Level Maths Trigonometric Ratios, covering 9.1 The Cosine Rule, 9.2 The Sine Rule, 9.3 Areas of Triangles, 9.4 Solving Triangle Problems, 9.5 Graphs of Sine, Cosine and Tangent, and 9.6 Transforming Trigonometric Graphs. Each one has a worked solution and a mark scheme showing where the marks go.