Divide.
-$( - 13 - 10 i ) \div ( 7 \mathrm { i } )$
A) $\frac { 10 } { 7 } + \frac { 13 } { 7 } \mathrm { i }$
B) $\frac { 10 } { 7 } - \frac { 13 } { 7 } \mathrm { i }$
C) $- \frac { 10 } { 7 } - \frac { 13 } { 7 } \mathrm { i }$
D) $- \frac { 10 } { 7 } + \frac { 13 } { 7 } \mathrm { i }$

Question

Quizplus · Accepted Answer

To divide by a complex number, multiply the numerator and denominator by the conjugate of the denominator. Here, multiply by $-7i$ to get $(-13 - 10i)(-7i) / (7i)(-7i)$. Simplifying gives $(-91 + 70i) / 49$, which results in $-\frac{10}{7} + \frac{13}{7}i$.

Divide - (−13−10i)÷(7i)( - 13 - 10 i ) \div ( 7 \mathrm { i } )(−13−10i)÷(7i)

Divide
- $( - 13 - 10 i ) \div ( 7 \mathrm { i } )$