Tìm (x), biết:

a) \(\left( {454 - x} \right) + {4^3} = 116\)

\(\left( {454 - x} \right) + 64 = 116\)

\(454 - x = 116 - 64\)

\(454 - x = 52\)

\(x = 454 - 52\)

\(x = 402\)

Vậy \(x = 402\).

b) \(51 - 3\left( {x + 2} \right) = 60\)

\(3\left( {x + 2} \right) = 51 - 60\)

\(3\left( {x + 2} \right) =  - 9\)

\(x + 2 =  - 3\)

\(x =  - 5\)

Vậy \(x =  - 5\).

c) \(2{\left( {x - 6} \right)^2} - 1 = 49\)

\(2{\left( {x - 6} \right)^2} = 49 + 1\)

\(2{\left( {x - 6} \right)^2} = 50\)

\(2{\left( {x - 6} \right)^2} = 50 : 25\)

\({\left( {x - 6} \right)^2} = 25\)

Trường hợp 1:

\(x - 6 = 5\)

\(x = 11\)

Vậy \(x \in \left\{ {11;1} \right\}\).

Trường hợp 2:

\(x - 6 =  - 5\)

\(x = 1\)