Question 1153137
P( 3, -1 )
M( 5, 4 )
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Find x-value of the other endpoint L( x, y )
{{{ ( 3 + x ) / 2 = 5 }}}
{{{ 3 + x = 10 }}}
{{{ x = 7 }}}
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{{{ ( -1 + y ) / 2 = 4 }}}
{{{ -1 + y = 8 }}}
{{{ y = 9 }}}
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L( x, y ), the other endpoint, is L( 7, 9 ) 
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check answer:
Find the equation that goes through P and L
{{{ ( y -(-1) ) / ( x - 3 ) = ( 9 -(-1) ) / ( 7 - 3 ) }}}
{{{ ( y + 1 ) / ( x - 3 ) = ( 9 + 1 ) / ( 7 - 3 ) }}}
{{{ ( y + 1 ) / ( x - 3 ) = 10 / 4 }}}
{{{ ( y + 1 ) / ( x - 3 ) = 5/2 }}}
{{{ 2*( y + 1 ) = 5*( x - 3 ) }}}
{{{ 2y + 2 = 5x - 15 }}}
{{{ 2y = 5x - 17 }}}
{{{ y = (5/2)*x - 17/2 }}}
Does the line go through M( 5,4 ) ?
{{{ 4 = ( 5/2 )*5 - 17/2 }}}
{{{ 4 = 25/2 - 17/2 }}}
{{{ 4 = 8/2 }}}
{{{ 4 = 4 }}}
OK