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

2 Answers
Jun 7, 2016

#3-71#

Explanation:

#(10-4i)-(7+3i)#
#color(white)("XXX")=color(red)(10-7color(blue)( -4i-3i)#

#color(white)("XXX")=color(red)(3)color(blue)(-7i)#

Jun 7, 2016

#3-7i#

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#.