ax^2+bx+c=0ax^2+bx=-cx^2+(b/a)x=-c/a(x+ b/(2a))^2 = -c/a + b^2/(4a^2)(x+ b/(2a))^2 = (b^2-4ac)/(4a^2)x= [-b±√(b^2-4ac) ]/ (2a)
