I was making up a chord progression on guitar which is F, E, Am, C.
I then attempted to find what key this progression could be in and I'm getting confused because I cannot find what key/scale contains an E major and an A minor.
I attempted to figure it out with an online tool http://musictheorysite.com/namethatkey/ and it claims that E major and A minor together are in the scale of A minor, but that's not true, an A minor scale contains
A minor, B diminished, C major, D minor, E minor, F major and G major, an E major is not present in the scale of A minor.
Are the chords E major and A minor simply not in scale even though they still sound good together?