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Subtract 3x – 7x3 + 5x2 from the sum of 2 + 8x2 – x3 and 2x3 – 3x2 + x - 2. |
| Answer» SIMPLIFY (6x3 – 2x2 + 8x) – (4x3 – 11x + 10)Here's the subtraction, done horizontally:(6x3 – 2x2 + 8x) – (4x3 – 11x + 10)(6x3 – 2x2 + 8x) – 1(4x3 – 11x + 10)(6x3 – 2x2 + 8x) – 1(4x3) – 1(–11x) – 1(10)6x3 – 2x2 + 8x – 4x3 + 11x – 106x3 – 4x3 – 2x2 + 8x + 11x – 102x3 – 2x2 + 19x – 10Going vertically, I'll write out the POLYNOMIALS, leaving gaps as necessary:\SMALL{ \begin{array}{rrrr}6x^3&-2X^2&+8x& \\4x^3& &-11x&+10\\ \hline \END{array} } 6x 3 4x 3 −2x 2 +8x−11x +10 Then I'll flip all of the signs in the second line, and then add down:\small{ \begin{array}{rrrr}6x^3&-2x^2&+8x& \\\textcolor{red}{\textbf{--}}4x^3& &\textcolor{red}{\textbf{+}}11x&\textcolor{red}{\textbf{--}}10\\ \hline 2x^3&-2x^2&+19x&-10\end{array} } 6x 3 –4x 3 2x 3 −2x 2 −2x 2 +8x+11x+19x –10−10 Either way, I get the same answer:2x3 – 2x2 + 19x – 10 | |