Need to read data from a file and draw points and connect the last 3?

Question

MATLAB

You need to read data from the file and draw points and connect the last 3 !!
something like this script in matlab

clear
A = load('data.txt'); % считываем данные
x = A(:,1); % первый столбец 
y = A(:,2); % второй столбец
plot(x,y,'o'); % рисуем
h=A(y(end)-2:y(end),1)
m=A(x(end)-2:x(end),1);
plot(m,h);

but nothing works