Question 425997
Use the general rule:
{{{ log(a*b) = log(a) + log(b) }}}
As an example of this rule,
{{{ log(10*1000) = log(10) + log(1000) }}}
or,
{{{ 4 = 1 + 3 }}}
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{{{ log(4x) = log(5)  + log(x-3) }}}
{{{ log(4x) = log((5*(x-3))) }}}
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Now use another general rule:
If {{{ log(a) = log(b) }}}, then
{{{a = b}}}
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{{{ 4x = 5*(x-3) }}}
{{{ 4x = 5x - 15 }}}
{{{ x = 15 }}}