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### Section 1-7 : Complex Numbers

3. Perform the indicated operation and write your answer in standard form.

$\left( {1 + 4i} \right) - \left( { - 16 + 9i} \right)$
Hint : You know how to do the operation with polynomials so you can do the operation here!
Show Solution

We know how to subtract two polynomials and so we also know how to subtract two complex numbers.

$\left( {1 + 4i} \right) - \left( { - 16 + 9i} \right) = 1 + 4i + 16 - 9i = \require{bbox} \bbox[2pt,border:1px solid black]{{17 - 5i}}$