Answer: A ) She only used the additive inverse of 10m when combining like terms .
Explanation:
Holly only used the additive inverse of 10m when combining like terms. The equality is erroneous because the equation was evaluated well. The calculations should be as follows:
11m -13n + 6mn - 10m + 7n - 3mn = 1m - 6n +3mn
She should have subtracted 13n and 7n then take the negative value. Also, subtract 6mn and 3mn.