Find the value of $x$ in each of the following a) $2 x-7=13$ b) $3 x+4=25$

Step 1 ：Given the equation \(2x - 7 = 13\), add 7 to both sides to get \(2x = 20\).

Step 2 ：Divide both sides of the equation \(2x = 20\) by 2 to get \(x = 10\).

Step 3 ：Given the equation \(3x + 4 = 25\), subtract 4 from both sides to get \(3x = 21\).

Step 4 ：Divide both sides of the equation \(3x = 21\) by 3 to get \(x = 7\).

Step 5 ：The solutions to the equations are \(x = 10\) for the first equation and \(x = 7\) for the second equation. So, the final answers are \(\boxed{10}\) and \(\boxed{7}\).