Holly finds that (11m - 13n + 6mn) - (10m - 7n + 3mn) = m - 20n + 9mn. What error did Holly make?

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

B.) She added the polynomials instead of subtracting.

C.) She only used the additive inverses of - 7n and 3mn when combining like terms.

D.) She did not combine all like terms.

Question

Desmond Livingston

Mathematics

30 July, 08:23

Holly finds that (11m - 13n + 6mn) - (10m - 7n + 3mn) = m - 20n + 9mn. What error did Holly make?

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

B.) She added the polynomials instead of subtracting.

C.) She only used the additive inverses of - 7n and 3mn when combining like terms.

D.) She did not combine all like terms.

+5

Answers (1)

Know the Answer?

Emmanuel Christian · Answer 1

The answer is A. 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.