Question 514774
Use the point-slope formula
{{{ ( 2 -(-4) ) / ( 3 - r ) = 3/2 }}}
{{{ 6 / ( 3 - r ) = 3/2 }}}
Multiply both sides by {{{ 2*( 3 - r) }}}
{{{ 12 = 3*( 3 - r ) }}}
{{{ 12 = 9 - 3r }}}
{{{ 3 = -3r }}}
{{{ r = -1 }}}
check answer:
{{{ ( 2 -(-4)) / ( 3 - r ) = 3/2 }}}
{{{ 6 / ( 3 -(-1) ) = 3/2 }}}
{{{ 6/4 = 3/2 }}}
{{{ 3/2 = 3/2 }}}
OK