Question

Which shows a quadratic function?

Answer 1

Answer:

OPTION B IS YOUR ANSWER.

You know its a quadratic when the second difference of each y value is same.

Here's what I mean.

Option B

First all x values differ by 1. So we're good on those.

Now for the y values

Which are

3, -1, -3, -3, -1

find the difference between the second and first fod each... Then do this a second time.

If it gives the same value for all the second differences... Then its quadratic.

-1-3 = -4

-3-(-1) = -3 + 1 = -2

-3-(-3) = -3 + 3 = 0

-1-(-3) = -1 + 3 = 2.

The values are -4, -2, 0, 2.

Now find the difference of these(2nd - 1st)

-2-(-4) = -2 + 4 = 2

0-(-2)= 0 + 2 = 2

2 - 0 = 2

Since all second differences gave 2 as their answer....

Option B is your Quadratic Function!!!

Hope this helps!