Which function is a quadratic function? c(x) = 6x + 3x3 d(x) = x – 8x4 p(x) = –5x – x2 k(x) = 2x2 + 9x4

Step-by-step explanation:

We know that a function is quadratic if the degree of the function is 2.

And we also know that the degree of a polynomial is the highest exponent.

So, we see which of the given options has the highest exponent as 2

Third option has the highest exponent 2. Hence, the degree of this function should be 2 and thus, it is a quadratic function.

assuming this is from a math graphing problem.

7 would be on the x-axis which is the horizontal line on the graph

84 would be on the y-axis which is the vertical line on the graph