For how many unique pairs of nonnegative integers {a, b} is the equation a^2 - b^2 = 99 true? Pick one: A) 1 B) 3 C) 5 D) 7 E) 9
Answer C   (a+b)(a-b)=99   3 cases For (a+b), (a-b)   99, 1   33, 3   11, 9   Answer 3
<result>B</result>
For how many unique pairs of nonnegative integers {a, b} is the equation a^2 - b^2 = 99 true?