# How do you simplify (10 - 4i) - (7 + 3i)?

Jun 7, 2016

$3 - 71$

#### Explanation:

$\left(10 - 4 i\right) - \left(7 + 3 i\right)$
color(white)("XXX")=color(red)(10-7color(blue)( -4i-3i)

$\textcolor{w h i t e}{\text{XXX}} = \textcolor{red}{3} \textcolor{b l u e}{- 7 i}$

Jun 7, 2016

$3 - 7 i$

#### Explanation:

You can sum two complex numbers simply by summing the real and imaginary parts.

The real part of the first number is $10$, the real part of the second one is $- 7$. Summing, you have $10 - 7 = 3$

Same goes for the imaginary parts: the imaginary coefficient of the first number is $- 4$, the coefficient of the second number is $- 3$ (remember that there's a minus sign in front of the whole expression!). Summing, you have $- 4 - 3 = - 7$.