Class 10

Math

All topics

Complex Number and Quadratic Equations

Which of the following is a quadratic equation ?

- $6x_{2}=20−x_{3}$
- $x_{2}(x_{2}1 )$ = $27 $
- $x3 $ $=4$ $x_{2}$
- $5x_{2}+7=3x$

$6x_{2}=20−x_{3}$

$x_{3}+6x_{2}−20=0$

In this, the maximum power of $x$ is $3$.

So, it is not quadratic equation.

Part $(B)$

$x_{2}(x_{2}1 )=27 $

$1=27 $

So, it is not quadratic equation.

Part $(C)$

$x3 =4x_{2}$

$3=4x_{3}$

In this, the maximum power of $x$ is $3$.

So, it is not quadratic equation.

Part $(D)$

$5x_{2}+7=3x$

$5x_{2}−3x+7=0$

In this, the maximum power of $x$ is $2$.

So, it is quadratic equation.

Hence, this is the answer.