SOLUTION: I have my placement test tomorrow and i have this example test which i can't solve. I need your help. For i=sqrt(-1), if 3i(2+5i)=x+6i, then x=?

Question 309266: I have my placement test tomorrow and i have this example test which i can't
solve. I need your help.
For i=sqrt(-1), if 3i(2+5i)=x+6i, then x=?
Found 2 solutions by Earlsdon, scott8148:
Answer by Earlsdon(6294) (Show Source): You can put this solution on YOUR website!
Solve for x:
Simplify the right side by multiplying.
Substitute
Subtract 6i from both sides.
so...

Answer by scott8148(6628) (Show Source): You can put this solution on YOUR website!
distributing ___ 6i + 15i^2 = x + 6i

subtracting 6i ___ 15i^2 = x ___ 15(-1) = x ___ -15 = x

good luck on the test
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