1)х2-17х-18=0
Д= 289-4×(-18)
Д= 289+72
Д=361
Д=19
×1= -(-17) +19/2=36/2=18
×2= -(-17) -19/2=-2/2=-1
х2 -8х+15=0
Д=64-(4×15)=64-60=4=2
×1= 8+2/2=5
×2= 8-2/2=6/2=3
1)х2-17х-18=0
Д= 289-4×(-18)
Д= 289+72
Д=361
Д=19
×1= -(-17) +19/2=36/2=18
×2= -(-17) -19/2=-2/2=-1
х2 -8х+15=0
Д=64-(4×15)=64-60=4=2
×1= 8+2/2=5
×2= 8-2/2=6/2=3