SOLUTION: That is log base 2 btw, Having a hard time figuring this out. log2 (x + 4) = 3 + log2 (x - 5)

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Question 341649: That is log base 2 btw, Having a hard time figuring this out.
log2 (x + 4) = 3 + log2 (x - 5)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
log2 (x + 4) = 3 + log2 (x - 5)
:
Subtract log2 (x-5) from both sides
log2 (x + 4) - log2 (x - 5) = 3
same as
log2(%28x%2B4%29%2F%28x-5%29) = 3
The exponent equiv
2%5E3 = %28x%2B4%29%2F%28x-5%29
8 = %28x%2B4%29%2F%28x-5%29
:
8(x-5) = x + 4
8x - 40 = x + 4
8x - x = 4 + 40
7x = 44
x = 44%2F7