Based on the indication, we can write this polynomial as below, k being a real number that we will have to identify (degree = 3 and we have three zeroes -3, -1, and 2).
We know that the point (1,10) is on the graph of this function, so we can say.
<span>draw a straight line through those points. that's your line of reflection. now you have only to figure out which of those equations corresponds to it. So it y=x</span>