In your notebook, set up the following addition using a vertical format and find the sum of the given polynomials. 3 x2 + 2 x - 5 and -4 + 7 x2 - x2 + 9 x - 9 21 x2 + 2 x + 20 10 x2 - 5 x - 1 10 x2 + 2 x - 9