The equation that deals with how far a projectile has traveled is called the **range
equation**. It deals with the X vector (*what's a vector?*) and how long the projectile has been in the air (the time of
flight, which we dealt with earlier).

This is the simplest equation that is involved with projectile motion:

range = Vox × Tf

range = (Vo × cos Ø) × Tf

The range of the projectile is equal to the X component of the initial velocity times
the cosine of the angle measure of the projectile multiplied by its time of flight. One of the ways to solve this equation is by using the time of flight equation, as discussed earlier. As in the time of flight equation, we replaced *Vox* with its respective vector equation in order of simplifying the math later on..