5x2+35x=0|÷5
x2+7x=0
D=b2-4ac=7^2-4×1×0=49
√D=7
x1= (-b-√D)/2a= (-7-7)/2= -7
x2=( -b+√D)/2a=(-7+7)/2=0
5x2+35x=0|÷5
x2+7x=0
D=b2-4ac=7^2-4×1×0=49
√D=7
x1= (-b-√D)/2a= (-7-7)/2= -7
x2=( -b+√D)/2a=(-7+7)/2=0