Evaluate modulus expression given equation

2 The solutions of the equation \(5 | x | = 5 - 2 x\) are \(x = a\) and \(x = b\), where \(a < b\).
Find the value of \(| 3 a - 1 | + | 7 b - 1 |\).

2 The solutions of the equation \(| 4 x - 1 | = | x + 3 |\) are \(x = p\) and \(x = q\), where \(p < q\).
Find the exact values of \(p\) and \(q\), and hence determine the exact value of \(| p - 2 | - | q - 1 |\).

2 Given that \(x\) satisfies the equation \(| 2 x + 3 | = | 2 x - 1 |\), find the value of $$| 4 x - 3 | - | 6 x |$$

2 It is given that \(x\) satisfies the equation \(| x + 1 | = 4\). Find the possible values of $$| x + 4 | - | x - 4 | .$$

4 It is given that \(| x + 3 a | = 5 a\), where \(a\) is a positive constant. Find, in terms of \(a\), the possible values of $$| x + 7 a | - | x - 7 a |$$