SOLUTION: how do i solve the equation log4x=log5 + log (x-3)

Algebra ->  Algebra  -> Logarithm Solvers, Trainers and Word Problems -> SOLUTION: how do i solve the equation log4x=log5 + log (x-3)      Log On

Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!
Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

   

Question 425997: how do i solve the equation
log4x=log5 + log (x-3)
Found 2 solutions by nerdybill, josmiceli:
Answer by nerdybill(6948) About Me  (Show Source):
You can put this solution on YOUR website!
log4x=log5 + log (x-3)
log4x=log5(x-3)
4x=5(x-3)
4x=5x-15
4x+15=5x
15 = x

Answer by josmiceli(9645) About Me  (Show Source):
You can put this solution on YOUR website!
Use the general rule:
+log%28a%2Ab%29+=+log%28a%29+%2B+log%28b%29+
As an example of this rule,
+log%2810%2A1000%29+=+log%2810%29+%2B+log%281000%29+
or,
+4+=+1+%2B+3+
--------------
+log%284x%29+=+log%285%29++%2B+log%28x-3%29+
+log%284x%29+=+log%28%285%2A%28x-3%29%29%29+
--------------
Now use another general rule:
If +log%28a%29+=+log%28b%29+, then
a+=+b
--------------
+4x+=+5%2A%28x-3%29+
+4x+=+5x+-+15+
+x+=+15+