Writing complex numbers in standard form

The video tutorial explains how to write complex numbers in standard form, which is expressed as A + BI, where A is the real part and BI is the imaginary part. The instructor demonstrates rewriting a complex number by separating the real and imaginary components. An announcement briefly interrupts the lesson, but the instructor resumes by showing how to express a negative square root as an imaginary number, completing the conversion to standard form.

How can the expression sqrt(-16) be rewritten?

What is the final standard form of the complex number discussed in the text?