When a song is in the key of C major, the Am chord will seamlessly intertwine with the tonic.  “Tonic” is a  fancy word for the root chord. It’s often referred to as the 1 chord, or the Roman numeral I chord. This chord is dependent upon the key signature of the song- in this case, C major.

We have learned every major key has one relative minor chord associated with it.  Am is the relative, or natural minor, for C.  The C major scale and the Am scale have the same exact notes, just different roots, so you can’t go wrong…

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5