x²+21x+80
a)x1+x2=-21, x1x2=80, x1=-5,x2=-16
x²+21x+80=(x+5)(x+16)
b)D=b²-4ac, b=21, a=1, c=80
D=441-320=121, √D=√121=11
x1=(-21+11)/2=-5 , x2=(-21-11)/2=-32/2=-16
x²+21x+80
a)x1+x2=-21, x1x2=80, x1=-5,x2=-16
x²+21x+80=(x+5)(x+16)
b)D=b²-4ac, b=21, a=1, c=80
D=441-320=121, √D=√121=11
x1=(-21+11)/2=-5 , x2=(-21-11)/2=-32/2=-16
x²+21x+80=(x+5)(x+16)