# does law of sines work for all triangles

## Best answer

The Law of Sines says that in any given triangle,the ratio of any side length to the sine of its opposite angle is the same for all three sides of the triangle. This is true for any triangle, not just right triangles. Full answer is here. Then, when can you use law of sines?

## People also ask

### What is the law of sines in geometry?

See also Law of Cosines. The Law of Sines says that in any given triangle, the ratio of any side length to the sine of its opposite angle is the same for all three sides of the triangle. This is true for any triangle, not just right triangles.

### Can the sine rule be used on any triangle?

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. Then, can Sohcahtoa be used on any triangle?

### What is the law of cosines for right triangles?

In particular, the law of cosines for right triangles reduces to just the familiar Pythagorean theorem. Indeed they do, but because sine and cosine are functions defined (in a sense) using right triangles, they become largely redundant in the cases of right triangles.

### How do you use the law of sines to prove congruence?

To use the Law of Sines you need to know either two angles and one side of the triangle (AAS or ASA) or two sides and an angle opposite one of them (SSA). Notice that for the first two cases we use the same parts that we used to prove congruence of triangles in geometry but in the last case we could not prove congruent triangles given these parts.