If the fractions ax/x+y, bx/x-y and c/2x+2y are rewritten as equivalent fractions with the lcd what form with.

The factors in the denominator are, respectively, (x + y), (x - y), 2, and (x + y) again.

To find the lcd, take each of the unique factors (to the highest power in which they appear).

The lcd is 2(x + y)(x - y).

hint:
lcd = 2(x+y)(x-y)