Since the pentatonic scale has five notes then there are five chord possibilities.
One major chord, one minor chord, two suspended chords (sus means to replace the 3rd with the 4th and sus2 means to replace the 3rd with the 2nd) and it turns out that the last chord is a minor augmented chord which is just the root major chord inverted.
Using C pentatonic as an example.
C pentatonic consists of C root, D 2nd, E 3rd, G 5th and A 6th.
C-E-G makes up C major
D-E-A is Dsus2
D-G-A is Dsus
E-C-G is an inversion of C major
G-A-D is Gsus2
G-C-D is Gsus
A-C-E makes A minor
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