SOLUTION: Log base 5 84= log base 5 (x-7) +log base 5 (x+1)

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Question 1157724: Log base 5 84= log base 5 (x-7) +log base 5 (x+1)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

log%285%2C84%29=+log%285%2C%28x-7%29%29+%2Blog%285%2C%28x%2B1%29%29
log%285%2C84%29=+log%285%2C%28x-7%29%28x%2B1%29%29......if log same then
84=+%28x-7%29%28x%2B1%29
84=+x%5E2+-+6+x+-+7
+x%5E2+-+6x+-+7-84=0
+x%5E2+-+6x++-+91=0
+x%5E2+%2B7x-+13x+-+91=0
+%28x%5E2+%2B7x%29-+%2813x+%2B91%29=0
+x%28x+%2B7%29-+13%28x+%2B7%29=0
%28x+-+13%29+%28x+%2B+7%29+=+0
solutions:
x=13-> your solution
x=-7-> disregard complex solution