SOLUTION: If 3i(2+5i)=x+6i,then x+= ?

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Question 124340: If 3i(2+5i)=x+6i,then x+= ?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If 3i(2+5i)=x+6i,then x+= ?
:
I assume you mean to just solve for x:
3i( 2 + 5i) = x + 6i
6i + 15(i^2) = x + 6i;
6i + 15(-1) = x + 6i; (i^2 = -1)
6i - 15 = x + 6i
subtract 6i from both sides:
-15 = x
:
:
Check solution in original equation:
3i( 2 + 5i) = -15 + 6i
6i + 15(i^2) = -15 + 6i
6i + 15(-1) = -15 + 6i
6i - 15 = -15 + 6i; confirms our solution