1. Speed = Wavelength x Frequency:

* Speed: The speed of the wave (usually measured in meters per second, m/s).

* Wavelength: The distance between two consecutive crests or troughs of the wave (measured in meters, m).

* Frequency: The number of wave crests or troughs passing a fixed point per second (measured in Hertz, Hz).

2. Speed = Distance / Time:

* Speed: The speed of the wave (measured in meters per second, m/s).

* Distance: The total distance travelled by the wave (measured in meters, m).

* Time: The time taken by the wave to travel the given distance (measured in seconds, s).

These equations are applicable to all types of waves, including sound waves, light waves, and water waves.