Tìm (x), biết:

a) \(255 - \left( {x + 9} \right) = 184\)

\(x + 9 = 255 - 184\)

\(x + 9 = 71\)

\(x = 71 - 9\)

\(x = 62\)

Vậy \(x = 62\).

b) \(9 + \left( {5x - 10} \right) = 4\)

\(5x - 10 = 4 - 9\)

\(5x - 10 =  - 5\)

\(5x =  - 5 + 10\)

\(5x = 5\)

\(x = 1\)

Vậy \(x = 1\).

c) \({\left( {x - 1} \right)^4} = 16\)

\({\left( {x - 1} \right)^4} = {2^4}\)

\({\left( {x - 1} \right)^4} = {\left( { - 2} \right)^4}\)

Trường hợp 1: \(x - 1 = 2\)

\(x = 2 + 1\)

\(x = 3\)

Trường hợp 2: \(x - 1 =  - 2\)

\(x =  - 2 + 1\)

\(x =  - 1\)

Vậy \(x \in \left\{ {3; - 1} \right\}\).