so for this you would have to use the pythagorean theorem which is α²+b²=c². The 12 yards would be a and the distance between the 60 yard line and 50 yard line which is 5 would be b and you would be trying to find out what c is.
a²+b²=c²
12²+5²=c²
144+25=c²
169=c²
now you want to get c alone and in order to do that we would square root it and i'm sure you have learned that what you do on one side you have to do to the other so we would also square root 169
√169=√c²
13=c
the pass was 13 yards
hope i helped :)
