Problem
1. What is the value of the expression below when $z^{\wedge} 2=-5$ ? Show the substitution. operation \[ z^{2}+3 z-7 \]
Solution
Step 1 ：Given the expression \(z^{2}+3 z-7\) and the condition \(z^{2}=-5\).
Step 2 ：Substitute \(z^{2}=-5\) into the expression, we get \(-5+3z-7\).
Step 3 ：Simplify the expression to get \(3z - 12\).
Step 4 ：So, the value of the expression \(z^{2}+3 z-7\) when \(z^{2}=-5\) is \(3z - 12\).
Step 5 ：\(\boxed{3z - 12}\) is the final answer.
