Oblicz a i b.
A = (3a,2)=(x_A,y_A)
B = (a,2b)=(x_B,y_B)
S = (b,a)=(x_S,y_S)
\left \{ {{x_S=\frac{x_A+x_B}{2}} \atop {y_S=\frac{y_A+y_B}{2}}} \right.
\left \{ {{b=\frac{3a+a}{2}} \atop {a=\frac{2+2b}{2}}} \right.
\left \{ {{b=\frac{4a}{2}} \atop {a=\frac{2(1+b)}{2}}} \right.
\left \{ {{b=2a} \atop {a=1+b}} \right.
podstawiam wyznaczone a
b=2(1+b)
b=2+2b
b-2b=2
-b=2
b=-2
podstawiam b
a=1+b=1+(-2)
a=-1
\left \{ {{a=-1} \atop {b=-2}} \right. <-- odpowiedź
A = (-3,2)
B = (-1,-4)
S = (-2,-1)