How do you simplify #(8+5i)(-6-2i)#?

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Answer 1 · 2018-08-11T18:07:48

#-38 - 46i#

#(8+5i)(-6-2i)#

Use FOIL to distribute/expand:
#8 * -6 = -48#

#8 * -2i = -16i#

#5i * -6 = -30i#

#5i * -2i = -10i^2#

Combine them together:
#-48 - 16i - 30i - 10i^2#

Combine like terms;
#-48 - 46i - 10i^2#

We know that #i^2 = -1#, so:
#-48 - 46i - 10(-1)#

Simplify:
#-48 - 46i + 10#

#-38 - 46i#

Hope this helps!