SOLUTION: How do I factor: z^2+25, over the set of complex numbers?

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Question 19323: How do I factor: z^2+25, over the set of complex numbers?
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
z^2+25=...since we are dealing with complex numbers we can write +25=-(25)*(-1)
=-(5*5)(i*i)=-(5i)^2...so we have.... z^2+25 =z^2-(5i)^2
using the formula (x+y)(x-y)=x^2-y^2..we get
z^2-(5i)^2=(z+5i)(z-5i)