Find a polynomial P (x) with real coefficients having a degree 4, leading coefficient 5, and zeros 3-i and 3i

The degree of 4 means that the highest exponent number will be 4 for example 4x^4, leading coefficient 5 means 5 will be the number in front of the degree of 4 so 5x^4 and for the polynomial to have those zeros all you would do is go back wards in the process of getting the zeros, so you would start with x=___ and x=___ from there you flip the signs of the zeros so what's positive becomes negative and what's negative becomes positive and keep going backwards from there