I believe the answer is x² + 3x - 10.
I found this on Yahoo Answers so it isn't my own work.
An example of quadratic equation with this behavior is:

Which is sketched at the end of this answer.
A quadratic equation has the format:

It's roots are given by:

The number of roots depends on the discriminant
, that is:
- If
, it has two different real roots. - If
, it has one real root. - If
, it has no real roots.
In this problem, it will have only positive y-values if:
and 
Thus, an example is:

Which is sketched below.
A similar problem is given at brainly.com/question/19776811
Answer:

Step-by-step explanation:
For easy calculations let's use the supplementary angles:






Now lets calculate the magnitude of the vector C:

where:


Finally:

The function f(x) shows how much Kate pays for the data service for downloading x songs in a month. So f(14) will represent the amount that Kate will have to pay for downloading 14 songs in a month.
f(x) = 2.50x + 11.50
Replacing x by 14, we get:
f(14) = 2.50(14) + 11.50 = 46.5
Thus, Kate will have to pay $ 46.5 for downloading 14 songs in a month