Does Sine Rule Apply to All Triangles?

The Sine Rule can be used in any triangle (not just right-angled triangles) where a side and its opposite angle are known. You will only ever need two parts of the Sine Rule formula, not all three. You will need to know at least one pair of a side with its opposite angle to use the Sine Rule.

Can you use sine on non-right triangles?

The Law of Sines can be used to solve oblique triangles, which are non-right triangles. According to the Law of Sines, the ratio of the measurement of one of the angles to the length of its opposite side equals the other two ratios of angle measure to opposite side.

Does Law of Sines and cosines work for all triangles?

Yes, the Law of Cosines works for all triangles. However, the proof depends on the shape a triangle, more precisely, how an altitude from some vertex falls onto the opposite side.