holly finds that (11m - 13n + 6mn)-(10m - 7n + 3mn)=m - 20n + 9mn. what error did holly make?\nshe only used…

holly finds that (11m - 13n + 6mn)-(10m - 7n + 3mn)=m - 20n + 9mn. what error did holly make?\nshe only used the additive inverse of 10m when combining like terms.\nshe added the polynomials instead of subtracting.\nshe only used the additive inverses of -7n and 3mn when combining like terms.\nshe did not combine all like terms.

holly finds that (11m - 13n + 6mn)-(10m - 7n + 3mn)=m - 20n + 9mn. what error did holly make?\nshe only used the additive inverse of 10m when combining like terms.\nshe added the polynomials instead of subtracting.\nshe only used the additive inverses of -7n and 3mn when combining like terms.\nshe did not combine all like terms.

Answer

Explanation:

Step1: Expand the expression

[ \begin{align*} &(11m - 13n+6mn)-(10m - 7n + 3mn)\ =&11m-13n + 6mn-10m + 7n-3mn \end{align*} ]

Step2: Combine like - terms

[ \begin{align*} &(11m-10m)+(-13n + 7n)+(6mn-3mn)\ =&m-6n + 3mn \end{align*} ]

Step3: Analyze Holly's error

Holly's result is (m - 20n+9mn). She only used the additive inverse of (10m) when combining like - terms. She did not correctly apply the additive inverse to (-7n) and (3mn).

Answer:

She only used the additive inverse of 10m when combining like terms.