They may seem like two very different things, but the two are very related. Whenever you look at a line of music you can compare it to a line graph. The x-axis would represent the time you play a pitch, and the y-axis would represent which pitch you play. Then when you put the two together you get a melody or song.
Another very important part of music is rhythm, without rhythm a melody would be unorganized and difficult to listen to. The rhythm is shown is by using different types of notes. Eachnote divides a beat or pulse. For example, normally, a whole note equals 4 beats, half note equals 2 beats, a quater note equals 1 beat, an eigthnote equals 1/2a beat, a sixteenth note equals 1/4 a beat, and ect. Without the system music would sound uneven, and there would be no way to record music and all song would be unwritten. All of this uses math because of the dividing of the beats. You have to be able to divide and count all of the notes correctly or else the song or melody won't sound right.
At the beginning of any line of music you will see two numbers on top of eachother. This is called a time signature, and without it it would be difficult to understand the music. The top number represents how many beats are in each measure(the space between two bar lines). The bottom number represents which type of note equals one beats. For example, when ever you see a four over a four you know that measure has four beats and the quater note gets one beat,when you see a six over an eight you know there a six beats and an eighth note gets one beat. This is very important to know so you are able to read the rythm and know how to divide up the beats of the notes.
These are just some ways math uses music. Without math in music everything would sound unorganized and wouldn't make any sense. This shows how two things that nobody associates with eachother can rely on one to exsit.