I wanted to sign up for some guitar lessons, the prerequisites for joining it are in the image attached. I know and understand most of the things mentioned except for the "dominant" scale mentioned. I was hoping if anyone here can explain what it is and provide a link to a lesson about it
There isn't one "dominant scale", but they do exist. Dominant scales are an interesting phenomena in music because they almost always have other names and the requirements are simple: be able to build a dominant 7th chord off the tonic so the scale needs to have a Major 3rd, Perfect 5th, and minor 7th in it.
The most popular dominant scale is the Phrygian dominant scale as it is a mode of the harmonic minor scale, but there are others such as the Aeolian dominant scale,Mixolydian mode which can be looked at as a dominant scale, and Lydian Dominant.
The prospective teacher either can't string a sentence together properly in English or is being pretentious. What should be there is — 'major, minor, dominant chords.
Can't think of a better reason for avoiding this teacher, or going along just to burst a bubble or two. Do you have a contact point?