The midpoint of AB is M(5, 6)M(5,6). If the coordinates of A are ((3,8), what are the coordinates of B?

Answer 1

Midpoint Formulas for x and y are

x(mid) = ( x1 + x2 ) / 2

y(mid) = ( y1 + y2 ) / 2

So if midpoint is ( 5 , 6 ) and point A is ( 3 , 8 )

then for x .....

5 = ( 3 + x2 ) / 2 ==> x2 = 7

and for y ....

6 = ( 8 + y2 ) / 2 ==> y2 = 4 Point B = ( 7 , 4 )

Check (3 + 7) / 2 = 5 and ( 8+ 4 )/2 = 6 ==> Midpoint ( 5 , 6 ) checks okay ! !

Answer 2