Patrick B. answered 06/05/20
Math and computer tutor/teacher
It is 37!!!
(6+i)(6-i) = 36 + -6i + 6i - (-1) <-- FOIL
36 + -6i + 6i +1 <--- subtracting is the same as adding the opposite
= 36 + 1 <-- 6i cancels;
= 37
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checks by DIVISION!!!
37 37 (6+i)
----- = ----------------- <--- rationalizes the denomiantor
6-i (6-i)(6+i)
= 37(6+i)/37 <--- uses the same product we found above
= 6+i <-- same complex number we started with