Question 684089
The conjugate si 8+2i; 
therefore,
(8-2i)(8+2i)
FOIL
8(8) + 8(2i) + -2i(8) + -2i(2i)
64 + 16i - 16i - 4i^2
...
Knowing i^2 = {{{sqrt(-1)^2 = -1}}}
...
64 - 4(-1)
64 + 4 = {{{highlight_green(68)}}}
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