Respuesta :

A quadratic function is of the form:

[tex]y=ax^2+bx+c[/tex]

That is, a function of degree 2.

- In this case, the function

[tex]3x^2+5x=0[/tex]

It is a function of degree 2, so it is a quadratic function.

- For the function

[tex]3x-5=0[/tex]

We see that it does not have a term of degree 2, therefore it is not a quadratic function.

- And for the function

[tex]y=3x^3+7x^2-9x[/tex]

It is a function of degree 3, therefore, it is not a quadratic function.

Answer:

[tex]3x^2+5x=0[/tex]