Double check my answer ?

after plotting the data where x represents the length of the side of a polygon, and f(x) represents the area of the polygon, jack used technology and constructed an appropriate model to approximate the area of the polygon. use the model jack created to predict the area of a polygon that has a side length of 3.
f(x) = x^2 + 3x + 1.

answers:
1. 10
2. 18
3. 19
4. 20

my answer = 18

correct?