The product of the squares of two positive integers is 81. How many pairs of positive integers satisfy this condition?
Choose the correct choice from the following:
A) 0 B) 1 C) 2 D) 3 E) 4
Ans: C - 2 pairs   (xˆ2)(yˆ2) = 81 [square root both sides]   xy = 9   9 = 1x9, 9x1, 3x3   Cancel the repeats   This leaves us with exactly 2 options.   Hence, 2
<result>C</result>
The product of the squares of two positive integers is 81. How many pairs of positive integers satisfy this condition?