3x^2+7.5x-27=3(x+4.5)(x-2)
D=256.25+324=380.25
x1=(-7.5-19.5)/6= -4.5
x2=(-7.5+19.5)/6=2
3x^2+10.5x-13.5=3(x+4.5)(x-1)
D=110.25+162=272.25
x1=(-10.5-16.5)/6= -4.5
x2=(-10.5+16.5)/6=1
(3x^2+7.5x-27)/(3x^2+10.5-13.5)=(3*(x+4.5)(x-2))/(3*(x+4.5)(x-1)=(x-2)/(x-1)