Hi, my name is Stefan. Today, I'm going to be speaking on how math is used by homicide detectives. In homicides the detectives always look for the shell casings of a bullet. This shell casing lets the detectives know where the shots was fired. The shooter shoots from his gun and it leaves a shell casing. And we also look at the angle of trajectory that the bullet went inside of the victim. This will be our victim here and the angle went this way. So we could draw a line. Now we have our angle theta. Now that we have this angle and we know where the shooter was we can now calculate the height of the shooter. And this gives us a clear description of the shooter and how tall he was. And where he was standing. And so this gives us more information about our homicide. And we can use the tangent formula, tangent of theta is equivalent to opposite this right here over D. This distance we'll call that D. They can use a measuring tape and get that distance. And this equation is used in all homicides and this helps the detectives find their perpetrator.