Which function is a quadratic function?

The function which is quadratic is:

We know that the general equation of a quadratic function is given by:

where a , b and c are real numbers.

1)

On solving we get:

Hence, the function is quadratic.

2)

It is not a quadratic equation since we have a term as :

and hence the equation will not match the general equation of the quadratic function.

3)

as it has a term of

Hence, it is a equation of a cubic function.

4)

On solving we get:

It does not has any term of

Hence, the equation is not a quadratic function it represent a linear function.

a) 0.25x times 3. (could be wrong on equation.)

b) 2.25 pound of dark chocolate. (can i eat all the chocolate? plz? anyway, again, could be wrong, but i hope im right. all the chocolate together should be 5.25 pounds)

have a good day!

answer:

a=9

step-by-step explanation: lmk if you need a explanation