Question 1087814
{{{ 5n = n^2 - 6 }}}
{{{ n^2 - 5n - 6 = 0 }}}
{{{ ( n - 6 )*( n + 1 ) = 0 }}} ( by looking at it )
{{{ n = 6 }}} ( the other solution gives me a negative result )
The number is 6
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check:
{{{ 6^2 - 5*6 - 6 = 0 }}}
{{{ 36 - 30 - 6 = 0 }}}
{{{ 36 - 36 = 0 }}}
OK