To solve the equation \( 7(x-4) + 3 = 3(2x-7) + x - 8 \), we will first simplify both sides.
Starting with the left side:
\[ 7(x - 4) + 3 = 7x - 28 + 3 = 7x - 25 \]
Now simplify the right side:
\[ 3(2x - 7) + x - 8 = 6x - 21 + x - 8 = 6x - 21 - 8 = 6x - 29 \]
Now we have:
\[ 7x - 25 = 6x - 29 \]
Next, we will isolate \(x\). To do this, subtract \(6x\) from both sides:
\[ 7x - 6x - 25 = -29 \]
This simplifies to:
\[ x - 25 = -29 \]
Now, add \(25\) to both sides:
\[ x = -29 + 25 \]
Therefore:
\[ x = -4 \]
The solution to the equation is:
\[ \boxed{-4} \]