1. If two of the expressions x+y, x+5y, x-y, and 5x-y are chosen at random, what is the probability that their product will be of the form of x2 - (by)2, where b is an integer?
a. ½
b. 1/3
c. /4
d. 1/5
e. 1/6
please note x2 = x square and (by)2 = by square
a. ½
b. 1/3
c. /4
d. 1/5
e. 1/6
please note x2 = x square and (by)2 = by square
