What's the Error? Explain the error. Find the correct solution.

19 + (-31) = 12

The answer is incorrect because 12 should be negative not positive.

Step-by-step explanation:

1. 19 + - 31 = - 12

2. Twelve is negative because if you were to start off at - 31 and add 19 the answer would remain negative since - 31 in a sense is "bigger" than 19. You would need more of a positive number to make - 31 positive such as 40.

40 + - 31 = 9