add-by-aligning-like-terms-vertically-5x3-2x-4-and-3x3-x2-7x-9-what-is-the-sum

Question

Add by aligning like terms vertically: 5x3+2x−$$45x^3 + 2x - 4  $$and 3x3−$$x2+7x+93x^3$$ - $$x^2 + 7x + 9. $$What is their sum?

Accepted Answer

8x3−$$x2+9x+58x^3$$ - $$x^2 + 9x + 5 $$

Answer

8x3−x2−$$5x+58x^3$$ - $$x^2 - 5x + 5 $$

Answer

2x3−$$x2+9x+52x^3$$ - $$x^2 + 9x + 5 $$

Answer

$$8x3+x2+9x+58x^3$$ + $$x^2 + 9x + 5 $$

Add by aligning like terms vertically: 5x3+2x−45x^3 + 2x - 4 and 3x3−x2+7x+93x^3 - x^2 + 7x + 9. What is their sum?