The polynomial -17x^2 + 165x + 14,481 represents the electricity generated​ (in gigawatts) by geothermal sources during 2002-2007. The polynomial 879x^2 - 72x + 10,140 represents the electricity generated​ (in gigawatts) by wind power during 2002-2007. In both​ polynomials, x represents the number of years after 2002. Find a polynomial for the total electricity generated by both geothermal and wind power during 2002-2007.