Which of the following is a quadratic equation?
(A)
(B)
(C)
(D)
(E) Both (C) and (D)
Quadratic equations are the equations of the form
where a, b and c are real numbers and
.
is not a quadratic equation because
in this case. It is a linear equation.
is not a quadratic equation because
in this case. It is also a linear equation.
is not a quadratic equation but it is a quadratic polynomial. To make it a quadratic equation, we will equate it to
. It means that
is a quadratic equation but
is not.
is of the form
and
. Therefore, it is a quadratic equation.
Hence, the answer is (D).
Leave a Reply