Answer:
4 appels if you dont get any but if you get one as well 3
Step-by-step explanation:
Answer:

Step-by-step explanation:
Let us consider the equation 
For a quadratic equation in a standard form,
, the axis of symmetry is the vertical line
.
Here in this case we have, 
Putting the values we get,

We can see that the axis of symmetry is x=3 and the graph is giving minimum at x=3.
Therefore, the required equation is
. Refer the image attached.
The common factor would be 3 because 3 is the highest multiple of 15 and 9