Simplify (-6x^3-4x^2-8)+(x^3-x^2-9x+4)

$(- 6 x^{3} - 4 x^{2} - 8) + (x^{3} - x^{2} - 9 x + 4)$

Step 1

Remove parentheses.

$- 6 x^{3} - 4 x^{2} - 8 + x^{3} - x^{2} - 9 x + 4$

Step 2

Add $- 6 x^{3}$ and $x^{3}$ .

$- 5 x^{3} - 4 x^{2} - 8 - x^{2} - 9 x + 4$

Step 3

Subtract $x^{2}$ from $- 4 x^{2}$ .

$- 5 x^{3} - 5 x^{2} - 8 - 9 x + 4$

Step 4

Add $- 8$ and $4$ .

$- 5 x^{3} - 5 x^{2} - 9 x - 4$