Question 1101590
Use {{{ 1 = log(( 10 )) }}}
{{{ log(( x+9 )) - log(( x )) = log(( 10 )) }}}
{{{ log( (( x+9 ) / x )) = log(( 10 )) }}}
{{{ ( x+9 )/x = 10 }}}
{{{ x + 9 = 10x }}}
{{{ 9x = 9 }}}
{{{ x = 1 }}}
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check:
{{{ log(( x+9 )) - log(( x )) = log(( 10 )) }}}
{{{ log(( 10 )) - log(( 1 )) = log(( 10 )) }}}
{{{ 1 - 0 = 1 }}}
OK