Note that he critisize the classical formula but that he, then, suppose that A=1 when he gives his formulation (making it simpler). Adding A back gives : -B/2A

Note that he critisize the classical formula but that he, then, suppose that A=1 when he gives his formulation (making it simpler). Adding A back gives : -B/2A ± sqrt(B²/4A - C/A) which is not obviously simpler than : (-B ± sqrt(B² - 4AC)) / 2A