The question is incomplete. The complete question is :
M and n are both integers. Select all the statements that are true if m and n are also equal to each other.
A. m - n = n - m
B. 0 = m - n
C. m + (-n) = m - n
D. m + n = 0
Answer :
A. m - n = n - m
B. 0 = m - n
C. m + (-n) = m - n
Explanation :
It is given that m and n are integers and they both are equal to each other.
i.e. m = n
Therefore for option (A),
m - n = n - m
m - m = m - m (since m and n are equal)
0 = 0
Therefore, the statement (A) is true.
For option (B),
0 = m - n
0 = m - m (since m and n are equal)
0 = 0
Therefore, the statement (B) is true.
For option (C),
m + (-n) = m - n
m + (-m) = m - m (since m and n are equal)
m - m = m - m
0 = 0
Therefore, the statement (C) is true.
Now for option (D),
m + n = 0
m + m ≠ 0 (since m and n are equal)
2m ≠ 0
Therefore, the statement (D) is false.
Hence, the options (A), (B) and (C) are true.