Tìm số nguyên \(x\), biết:

f) \(51 + 2\left( {3x - 5} \right) = 5\).

g) \[26 \cdot \left( {74 - 126} \right) - 74 \cdot \left( {126 + 26} \right)\]

\[ = 26 \cdot 74 - 26 \cdot 126 - 74 \cdot 126 - 74 \cdot 26\]

\[ = \left( {26 \cdot 74 - 74 \cdot 126} \right) - \left( {26 \cdot 126 + 74 \cdot 26} \right)\]

\[ = 74 \cdot \left( {26 - 126} \right) - 26 \cdot \left( {126 + 74} \right)\]

\[ = 74 \cdot \left( { - 100} \right) - 26 \cdot 200\]

b) \[\left( { - 25} \right) \cdot 8 \cdot \left( { - 125} \right) \cdot 3 \cdot \left( { - 4} \right)\]

\( = \left[ {\left( { - 25} \right) \cdot \left( { - 4} \right)} \right] \cdot \left[ {8 \cdot \left( { - 125} \right)} \right] \cdot 3\)

\[ = 100 \cdot \left( { - 1\,\,000} \right) \cdot 3\]