Answer:
w^2 + 13w + 39
Explanation:
Multiplying Polynomials (FOIL- Firsts, Outs, Inners, Lasts)
(w+9) (w+4) Multiply- Firsts (w*w) Outs (w*4) Inners (9*w) Lasts (9*4)
w*w + w*4 + 9*w + 9*4 Multiply the FOIL
w^2 + 4w + 9w + 36 Combine like terms (same variables, numbers)
w^2 + 13w + 39