Odpowiedź:
S = ( 13 , - 2 ) , A = ( - 7 , 4 ) , B = (xb , yb)
xs = 13 , xa = - 7 , ys = - 2 , ya = 4
xs = (xa + xb)/2
2 * xs = xa + xb
xb = 2 * xs - xa = 2 * 13 - (- 7) = 26 + 7 = 33
ys = (ya + yb)/2
2 * ys = ya + yb
yb = 2 * ys - ya = 2 * (- 2) - 4 = - 4 - 4 = - 8
B = ( 33 , - 8 )
Odp: D
