SOLUTION: z-3/z+5= 2/7

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Question 354221: z-3/z+5= 2/7
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
z-3/z+5= 2/7
z-3/z=2/7-5
(z*z-3)/z=(2-5*7)/7
(z^2-3)/z=(2-35)/7
(z^2-3)/z=-33/7 cross multiply.
7(z^2-3)=-33z
7z^2-21+33z=0
7z^2-33z-21=0
Ans. using: z+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ IS (5.28 & -.568).
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Unless you mean:
(z-3)/(z+5)= 2/7 Then:
7(z-3)=2(z+5)
7z-21=2z+10
7z-2z=10+21
5z=31
z=31/5
z=6.2 ans.