Answer:
- x = -10 1/6
 - x = 24 3/5
 - x = -7 1/4
 
Explanation:
The relevant rules of logarithms are ...
 log(a)+log(b) = log(ab)
 log(a)-log(b) = log(a/b)
The base of the logarithm doesn't matter, as long as all bases are the same.
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In each case, we can simplify the left side to a single log, then take the antilog and finish solving the linear equation.
1. log(3-x) +log(6) = log(79)
 log(6(3-x)) = log(79)
 6(3 -x) = 79
 3 -x = 79/6
 x = 3 -79/6
 x = -10 1/6
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2. log(5x +3) -log(2) = log(63)
 log((5x+3)/2) = log(63)
 (5x +3)/2 = 63
 5x +3 = 126
 5x = 123
 x = 24.6
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3. log(-4x -7) +log(2) = log(44)
 log(2(-4x-7)) = log(44)
 2(-4x -7) = 44
 4x +7 = -22
 4x = -29
 x = -7 1/4