# The Sine Rule

Let us now look at the Sine Rule

Objectives
 At the end of the lesson we should be able to state the sine rule apply Sine Rule to calculate the lengths of sides of an angle apply Sine Rule to calculate the sizes of angles apply Sine Rule to solve word problems

The sine rule is an important rule relating the sides and angles of any triangle (it doesn't have to be right-angled!):

If a, b and c are the lengths of the sides opposite the angles A, B and C in a triangle, then: A triangle