Find the LCD of the pair of expressions.

start fraction 3 m over m plus n end fraction; start fraction 3 n over m minus n end fraction

A. Left parenthesis m plus n right parenthesis times left parenthesis m minus n right parenthesis
B. 2 m
C. 2 m n
D. left parenthesis m minus n right parenthesis squared

1 answer

The denominators of the two expressions are (m+n) and (m-n). The LCD is the product of these two factors, so the answer is:

A. (m+n)(m-n)