# Math

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For i = the square root of -1, if 3i (2 + 5i) = x + 6i, then x = ?

A. –15
B. 5
C. 5i
D. 15i
E. 27i

• Math -

we will be happy to critique your thinking.

• Math -

Simplify the left hand side (LHS) from
3i(2+5i)
= 6i + 15i2
= 6i - 15
Equate to the RHS and solve for x.

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