Question 1123105
{{{ sqrt( 43 - n ) = n - 1 }}}
Square both sides
{{{ 43 - n = ( n - 1 )^2 }}}
{{{ 43 - n = n^2 -2n + 1 }}}
{{{ n^2 - n - 42 = 0 }}}
{{{ ( n - 7 )*( n + 6 ) = 0 }}}
C) {7}
{{{ -6 }}} does not work because you have
to take the negative square root