If \(16x^4 - 24x^3 + (a - 1)x^2 + (b + 1)x + 49\) is a perfect square, find the values of \(a\) and \(b\).
 
Answer:
 
The value of \(a =\) .
 
The value of \(b =\) .
 
(Note: Insert negative sign if necessary.)