SOLUTION: log base 3(5z+5) - Log base 3(z^2-1)=0

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Question 1008878: log base 3(5z+5) - Log base 3(z^2-1)=0
Answer by ikleyn(52858) About Me  (Show Source):
You can put this solution on YOUR website!
.
log%283%2C%285z%2B5%29%29 - log%283%2C%28z%5E2-1%29%29 = 0   -----> 

log%283%2C%285z%2B5%29%29 = log%283%2C%28z%5E2-1%29%29   ----->

5z+%2B+5 = z%5E2-1   ----->

z%5E2+-+5z+-6 = 0   ----->   (factor)   ----->

(z-6)*(z+1) = 0   ----->

z%5B1%5D = 6, z%5B2%5D = -1.

The root z%5B2%5D doesn't suit the original equation (why ?).

The only solution of the original equation is z = 6.