Question

pls help

For z = -3 + 5i, evaluate $z \overline{z}.$
(Note: $\overline{z}$ denotes the conjugate of z.)

Answer 1

Answer:

$\underline{ \boxed{z\overline{z} = 34}}$

Step-by-step explanation:

$if \: z = -3 + 5i \\then \: \overline{z} = - (3 + 5i) \\ hence \: z\overline{z} = (-3 + 5i)( - 3 - 5i) \\ z\overline{z} = 9 + 15i - 15i - {(5i)}^{2} \\ z\overline{z} = 9 - (25 ){i}^{2} \\ z\overline{z} = 9 - (25)( - 1) \\ z\overline{z} = 9 + 25 \\ \underline{ \boxed{z\overline{z} = 34}}$

♨Rage♨

Answer 2

Answer:

34

Step-by-step explanation:

Here z = -3 + 5i and the complement of this is

        z-comp = -3 - 5i.

Multiplying these two quantities together, we get

9 -25i²   =    9 + 25  =  34