To expand the expression \( 4(3z - 7) \), you need to distribute the \( 4 \) to both terms inside the parentheses:
\[ 4(3z) - 4(7) \]
Calculating each term:
\[ 4 \cdot 3z = 12z \] \[ 4 \cdot 7 = 28 \]
Putting it all together, the expanded expression is:
\[ 12z - 28 \]
So, \( 4(3z - 7) = 12z - 28 \).