SOLUTION: how do i find imaginary answers??? Find all real or imaginary solutions to each equation 78. W^2 = -225

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Question 59824: how do i find imaginary answers???
Find all real or imaginary solutions to each equation
78. W^2 = -225
Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
An imaginary number takes the form:
(i)(i)=-1, because %28sqrt%28-1%29%29=i,
In the real number world, the square root of a negative number cannot exist.
Example: (2)(2)=4 and the sqrt(4)=2
Example: (-2)(-2)=4 and the sqrt (4)=-2
When you multiply a number twice, the result will always be a positive number.
.
W^2 = -225
%28sqrt%28w%5E2%29%29=%28sqrt%28-225%29%29[Take the square root of both sides]
%28sqrt%28w%5E2%29%29=%28sqrt%28%28-1%29%28225%29%29%29
%28w%29%29=%2815sqrt%28-1%29%29
w=15i