(6x^2+5x-3)+(x^2-9) find the sum please

Ineed to know the answer to this algebra question.

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?

Answer asap! show all work! find the number of complex roots, the possible number of real roots and the possible rational roots of the polynomial function. then, solve for all roots. x^3 + 2x^2 + 3x + 6 = 0