Verified answer

(1.3x^3+4.3x^2-3.4x)-(-4.3x^3-4.6x^2+13)

1.3x^3 + 4.3x^2 - 3.4x + 4.3x^3 + 4.6x^2 - 13

5.6x^3 + 8.9x^2 - 3.4x -13

x(5.6x^2 + 8.9x - 3.4) - 13

(57770xxxxx45^45.223)