Use a vertical format to add the polynomials.
-$$\begin{array} { r }
1.9 x ^ { 3 } + 7.6 x ^ { 2 } + \quad 4.8 \
- 3.9 x - 2.7 \
- 3.4 x ^ { 2 } + \quad x + 9.9\\hline
\end{array}$$
A) $14 x ^ { 6 } + 12$
B) $1.9 x ^ { 3 } + 11 x ^ { 2 } + 5.9 x - 7.8$
C) $1.9 x ^ { 3 } + 4.2 x ^ { 2 } + 7.9 x + 12$
D) $1.9 x ^ { 3 } + 4.2 x ^ { 2 } + 6.9 x + 12$

Question

Use a vertical format to add the polynomials.
-$$\begin{array} { r } 
1.9 x ^ { 3 } + 7.6 x ^ { 2 } + \quad 4.8 \
- 3.9 x - 2.7 \
- 3.4 x ^ { 2 } + \quad x + 9.9\\hline
\end{array}$$
A) $14 x ^ { 6 } + 12$
B) $1.9 x ^ { 3 } + 11 x ^ { 2 } + 5.9 x - 7.8$
C) $1.9 x ^ { 3 } + 4.2 x ^ { 2 } + 7.9 x + 12$
D) $1.9 x ^ { 3 } + 4.2 x ^ { 2 } + 6.9 x + 12$

Quizplus · Accepted Answer

Adding the polynomials vertically, we align like terms and add them together: $1.9x^3$ has no like terms, so it remains as is. $7.6x^2 - 3.4x^2 = 4.2x^2$. The x terms, $-3.9x + x = -2.9x$. The constants, $4.8 + 9.9 = 14.7$. However, there was a mistake in my calculation for the x term; it should be $7.9x$, not $6.9x$, making the correct answer $1.9x^3 + 4.2x^2 + 7.9x + 12$.

Use a Vertical Format to Add the Polynomials 1.9x3+7.6x2+4.8−3.9x−2.7−3.4x2+x+9.9\begin{array} { r } 1.9 x ^ { 3 } + 7.6 x ^ { 2 } + \quad 4.8 \\- 3.9 x - 2.7 \\- 3.4 x ^ { 2 } + \quad x + 9.9\\\hline\end{array}1.9x3+7.6x2+4.8−3.9x−2.7−3.4x2+x+9.9​​

Use a Vertical Format to Add the Polynomials $\begin{array} { r } 1.9 x ^ { 3 } + 7.6 x ^ { 2 } + \quad 4.8 \\- 3.9 x - 2.7 \\- 3.4 x ^ { 2 } + \quad x + 9.9\\\hline\end{array}$