Use a vertical format to subtract the polynomials.
-$\begin{array} { c }
0.07 y ^ { 3 } - 0.09 y ^ { 2 } + 0.05 y \
- \left( 0.05 y ^ { 3 } - 0.06 y ^ { 2 } - \quad y \right)\\hline
\end{array}$
A) $0.2 y ^ { 3 } - 0.15 y ^ { 2 } + 0.06 y$
B)0. $0.02 y ^ { 3 } - 0.03 y ^ { 2 } + 1.05 y$
C) $0.02 y ^ { 3 } - 0.15 y ^ { 2 } - 0.95 y$
D) $0.2 y ^ { 3 } - 0.03 y ^ { 2 } + 0.04 y$

Question

Use a vertical format to subtract the polynomials.
-$\begin{array} { c } 
0.07 y ^ { 3 } - 0.09 y ^ { 2 } + 0.05 y \
- \left( 0.05 y ^ { 3 } - 0.06 y ^ { 2 } - \quad y \right)\\hline
\end{array}$
A) $0.2 y ^ { 3 } - 0.15 y ^ { 2 } + 0.06 y$
B)0. $0.02 y ^ { 3 } - 0.03 y ^ { 2 } + 1.05 y$
C) $0.02 y ^ { 3 } - 0.15 y ^ { 2 } - 0.95 y$
D) $0.2 y ^ { 3 } - 0.03 y ^ { 2 } + 0.04 y$

Quizplus · Accepted Answer

Subtracting the polynomials vertically, we add the opposite of the second polynomial to the first. This results in $0.07y^3 - 0.09y^2 + 0.05y + 0.05y^3 - 0.06y^2 + y = 0.12y^3 - 0.15y^2 + 1.05y$, which is not an option, indicating a mistake in my calculation. Correctly, it should be $0.07y^3 - 0.09y^2 + 0.05y - (0.05y^3 - 0.06y^2 - y) = 0.02y^3 - 0.03y^2 + 1.05y$, which matches option B.

Use a Vertical Format to Subtract the Polynomials 0.07y3−0.09y2+0.05y−(0.05y3−0.06y2−y)\begin{array} { c } 0.07 y ^ { 3 } - 0.09 y ^ { 2 } + 0.05 y \\- \left( 0.05 y ^ { 3 } - 0.06 y ^ { 2 } - \quad y \right)\\\hline\end{array}0.07y3−0.09y2+0.05y−(0.05y3−0.06y2−y)​​

Use a Vertical Format to Subtract the Polynomials $\begin{array} { c } 0.07 y ^ { 3 } - 0.09 y ^ { 2 } + 0.05 y \\- \left( 0.05 y ^ { 3 } - 0.06 y ^ { 2 } - \quad y \right)\\\hline\end{array}$