Any sources that discuss this viewpoint wrt the determinant? Seems I'm still at the "seemingly-arbitrary number" stage.
Do be warned that Algebra is a... high-octane... text written for serious math students and can be... powerful.
TL;DW the determinant represents how much you scale the area/volume/hypervolume (depending on dimension) of a shape by applying a matrix transformation to each point.
[0] https://www.youtube.com/watch?v=fNk_zzaMoSs&list=PLZHQObOWTQ...
[1] https://www.youtube.com/watch?v=Ip3X9LOh2dk&list=PLZHQObOWTQ...