Identify the real and imaginary parts of each complex number.
$-4-9i$

• A. $a = -9, b = -4$
• B. $a = -4, b = -9$
• C. $a = 4, b = 9$
• D. $a = -4, b = 9$

Answer: (B)

Verified step by step guidance

1. Recall that a complex number is generally written in the form \(a + bi\), where \(a\) is the real part and \(b\) is the imaginary part coefficient.
2. Identify the given complex number, which is \(-4 - 9i\). Here, the term without \(i\) is \(-4\), and the term with \(i\) is \(-9i\).
3. The real part \(a\) is the coefficient of the term without \(i\), so in this case, \(a = -4\).
4. The imaginary part \(b\) is the coefficient of the term with \(i\), so here, \(b = -9\).
5. Therefore, the complex number \(-4 - 9i\) has real part \(a = -4\) and imaginary part \(b = -9\).