Question

Como resolver 7x²-21x=0 por delta

Answer 1

7x²-21x=0
D=(-21)²-4.7.0
D=441-0
D=441

X=21±raiz de 441/2.7
X=21±21/14
X=42/14
X=3

X''=0/14
X''=0

S={0,3}

Answer 2

7x^2-21x=0
delta=b^2-4ac
delta=(-21)^2-4.7.0
delta=441-0
delta=441
x=-b-/+ raiz de delta/2a
x=-(-21)-21/2.7
x=21-21/14
x=0/14
x=0
x=-(-21)+21/2.7
x=21+21/14
x=42/14
x=3
S={0, 3}