x^2-4x+3=0
delta= b^2-4ac
delta=16-4*1*3
delta=16-12
delta=4
x1=(-b-rad delta)/2a
x1=4-2/2
x1=2/2
x1=1
x2=(-b+rad delta)/2a
x2=4+2/2
x2=6/2
x2=3
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x^2+2x-35=0
delta= b^2-4ac
delta=4-4*1*(-35)
delta=4+140
delta=144 => rad din delta=12
x1=(-b-rad delta)/2a
x1=-2-12/2
x1=-12/2
x1=-6
x2=(-b+rad delta)/2a
x2=-2+12/2
x2=10/2
x2=5