solve the equation:

log base 10 of x - log base 10 of (7-4x)=2

Please help i have been stuck on this for awhile!

4 answers

x/(7-4x) = 10^2

x = 100(7-4x)
x = 7400 -400x
401x = 7400
x = 7400/401
But in log (7-4x)
since we can only take logs of positives,
7-4x > 0
-4x > -7
x< 7/4 or x < 1.75

since 7400/401 > 1.75

there is no solution to this equation.
actually, the typos above conceal the fact that

x = 100(7-4x)
x = 700 - 400x
x = 700/401 which is in fact less than 7/4
Egg on face
(intentions were honourable)