2\(^7\) + ( x - 3\(^7\) ) = 5\(^7\) - 4\(^7\)

3 \(^x\) - (x + 2 \(^x\)) = 7

7 \(^2\) - (15 + x) = 5.2 \(^2\)

7 \(^3\) - 7(13 - x) = 14

-2/5 : \(1\dfrac{1}{3}\)- ( 1/2 )\(^2\)

\(\left(\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{5}{6}\right).\left(\dfrac{-3}{2}\right)^2\)

\(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)