Question 1131156
A segment has a midpoint at ({{{2}}}, {{{-7}}}) and an endpoint at ({{{8}}}, {{{-5}}}).
 What are the coordinates of the other endpoint?

Notice that the midpoints are the average of the coordinate. 

the other endpoint ({{{x}}},{{{y}}}) coordinates will be

 {{{2=(8+x)/2}}}
{{{4=8+x}}}
{{{x=-4}}}

{{{-7=(-5+y)/2}}}
{{{-14=-5+y}}}
{{{-14+5=y}}}
{{{-9=y}}}

the other endpoint is at ({{{x}}},{{{y}}})=({{{-4}}},{{{-9}}})



{{{ drawing( 600, 600, -10, 10, -10, 10,
circle(2,-7,.12),circle(-4,-9,.12), circle(8,-5,.12),
line(-4,-9,8,-5), locate(2,-7,M(2,-7)),locate(-4,-9,p(-4,-9)),locate(8,-5,p(8,-5)),
 graph( 600, 600, -10, 10, -10, 10, 0)) }}}