Answer:
18-5i
B is correct.
Step-by-step explanation:
Given: \(18-\sqrt{-25}\)
Simplify the given expression
Inside the square root negative number.
Using complex concept.
\(\sqrt{-1}=i\)
\(\sqrt{-25}=\sqrt{25}\cdot\sqrt{-1}\)
\(\sqrt{-25}=5i\)
Substitute the value into original equation.
\(18-\sqrt{-25}\Rightarrow 18-5i\)
Hence, The equivalent expression is 18-5i
