7)2x^2-3x+4=0
S=x1+x2=-b/2a=3/4
P=x1*x2=c/a=4/2=2
x^2+4x-5=0
S=x1+x2=-b/2a=-4/2=-2
P=x1*x2=c/a=5/1=5
2x^2-6x-5=0
S=6/4
P=5/2
Baftă!
