Question

Please can someone help me ?

Answer 1

Answer:

-3-5i

Step-by-step explanation:

Answer 2

z = -14 + 21i / -2 - 4i

Rectangular form:

z = -14-14.5i

Exponential form:

z = 20.155644 × ei (-133°59'42″)

Polar form:

z = 20.155644 × (cos (-133°59'42″) + i sin (-133°59'42″))

Polar form - absolute value (modulus) and angle (argument):

r = |z| = 20.15564

φ = arg z = -133.99491° = -133°59'42″ = -0.74442π

Calculation steps

   Divide: 21i / (-2) = -10.5i

   Add: -14 + (-10.5i) = -14-10.5i

   Subtract: (-14-10.5i) - 4i = -14 + (-10.5-4)i = -14-14.5i