M(-5;-8)
N(9;4)
x_(A)=(x_(M)+λx_(N))/(1+λ)=(-5+(1/3)*9)/(1+(1/3))=-3/2
y_(A)=(y_(M)+λy_(N))/(1+λ)=(-8+(1/3)*4)/(1+(1/3))=-5
A(-1,5;-5)
MB/BN=2/3
x_(B)=(x_(M)+λx_(N))/(1+λ)=(-5+(2/3)*9)/(1+(2/3))=3/5
y_(B)=(y_(M)+λy_(N))/(1+λ)=(-8+(2/3)*4)/(1+(2/3))=-16/5
B(3/5;-16/5)