The image shows a ray of light bending at the boundary of a glass block. According to a law of optics, sin i / sin r = n, where n is a consent. Which equation states the same law in terms of a and b?

The image shows a ray of light bending at the boundary of a glass block. According to a law of optics, sin i / sin r = n, where n is a consent. Which equation states the same law in terms of a and b?