What is the value of a^4 - b^4?
Statement(1) a^2 - b^2 = 16
Statement(2) a + b = 8
Source: GMATPrep
Answer: C
Statement(1) a^2 - b^2 = 16
Statement(2) a + b = 8
Source: GMATPrep
Answer: C
1) a²-b²= 16
(a+b) (a-b) = 16 = 2*2*2*2 = 8*2 or 4*4
(a+b) = 8 and (a-b) = 2
a = 5 b = 3
Sufficient
But it is not given that a and b are integers
