Find the product of -5 – 4i and its conjugate. The answer is a + bi where

Given complex number is (-5 - 4i).

Therefore, conjugate of this number will be (-5 + 4i)

[Conjugate of a complex number (a + bi) is (a - bi)]

Multiplication of the number and the conjugate of this number will be,

(-5 - 4i)(-5 + 4i) = (-5)² - (4i)²

                        = 25 - (16i²)

                        = 25 - (16)(-1) [Since, i² = (-1)]

                        = 25 + 16

                        = 41

It can be written in the form a complex form → (41 + 0.i)

Therefore, a = 41 and b = 0.

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Step-by-step explanation:

(-5 - 4i)(-5 + 4i)

25 - 20i + 20i - 16 i^2

25 + 16

41 + 0i

option: d is correct

step-by-step explanation:

4 + 5 7/9= 9 7/9

step-by-step explanation: