solve practical problems requiring the calculation of side lengths or angles in non-right-angled triangles using the sine rule or the cosine rule as appropriate
U2.AoS4.11
calculate the perimeter and areas of triangles (calculating the areas of triangles in practical situations using the rules A=1/2 bh, A=1/2 ab sin(c) or A=\sqrt{s(s-a)(s-b)(s-c)} where s=(a+b+c)/2
