Given: n2 + 4n = 0 and n = 0, –2, –4
On substituting n = 0 in L.H.S. of the given equation, we get:
(0)2 + 4(0)
= 0
L.H.S. = R.H.S.
Thus, n = 0 satisfies the given equation.
Therefore, n = 0 is a root of the given quadratic equation.
On substituting n = –2 in L.H.S. of the given equation, we get:
(–2)2 + 4(–2)
= 4 – 8
= – 4
L.H.S. R.H.S.
Thus, n = –2 does not satisfy the given equation.
Therefore, n = –2 is not a root of the given quadratic equation.
On substituting n = – 4 in L.H.S. of the given equation, we get:
(–4)2 + 4(–4)
= 16 – 16
L.H.S. = R.H.S.
Thus, n = – 4 satisfies the given equation.
Therefore, n = – 4 is a root of the given quadratic equation.