Add the Polynomials $5 p ^ { 2 } + 4 p + 15 \text { and } - 5 p ^ { 2 } - 9 p + 10$

Add the polynomials. $5 p ^ { 2 } + 4 p + 15 \text { and } - 5 p ^ { 2 } - 9 p + 10$