n – 3 = 4n

(vi) n – 3 = 4n

Sol. n – 3 = 4n

∴  n – 4n – 3 = 0

∴  – 3n – 3 = 0

changing the sign,

∴ 3n – 3 = 0

Here the maximum index of the variable n is 1.

So it is not a quadratic equation.