Question

Select all of the following that are quadratic equations.

Answer 1

Answer:

The quadratic equations are $7x^2 + 14x = 0$, $x^2 + 3x -5 = 0$  and $x^2 - x = 3x + 7$.

Step-by-step explanation:

Consider the provided information.

We need to find all the quadratic equations.

The given equations are:

$7x^2 + 14x = 0$

$x^3 - 3x^2 + 1 = 0$

$5x - 7 = 0$

$x^2 + 3x -5 = 0$

$x - 5 = 9x + 7$

$x^2 - x = 3x + 7$

Quadratic equations is an equation of the second degree (degree is the highest power of x).

Now consider the provided options:

The equations having second degree are:

$7x^2 + 14x = 0$ The highest power of x is 2.

$x^2 + 3x -5 = 0$ The highest power of x is 2.

$x^2 - x = 3x + 7$ The highest power of x is 2.

Hence, the quadratic equations are $7x^2 + 14x = 0$, $x^2 + 3x -5 = 0$  and $x^2 - x = 3x + 7$.

Answer 2

A quadratic equation has to have x^2....it does not necessarily have to have a constant.

7x^2 + 14x = 0
x^2 + 3x - 5 = 0
x^2 - x = 3x + 7
these are quadratic