Log по основанию 6 (х+11)=log по основанию 7 (х+11)

$displaystyle log_6(x+11)=log_7(x+11);$

$displaystyle frac{log(x+11)}{log(6)}=frac{log(x+11)}{log(7)};$

$displaystyle log(x+11)log(7)=log(x+11)log(6);$

$displaystyle log(x+11)log(7)-log(x+11)log(6)=0;$

$displaystyle log(x+11)left(log(7)-log(6)right)=0;$

$displaystyle log(x+11)=0;$

$displaystyle x+11=1;$

$displaystyle therefore{x=boxed{-10}phantom{.}}.$