Respuesta :

Answer :

m = 13.4/4.65

Step by step :

7.8 + 2(0.75m + 0.4) = -6.4m + 4(0.5m - 0.8)

7.8 + 2.75m + 0.8 = -6.4m + 4.5m - 4.8

2.75m + 6.4m - 4.5m = -7.8 - 0.8 - 4.8

4.65m = 13.4

m = 13.4/4.65

Answer:

B

Step-by-step explanation:

She is incorrect because when substituting 2 for m the result was a false statement.