x = [1 2 4 5]'
y = [6 4 2 3]'
%% f(x) = ax + b kozelites
A = x;
A(:,2) = ones(4,1)
A\y % teszt: ismeri-e?
(A'*A)\(A'*y)
% fuggveny: -0.8x + 6.15
% abrazoljunk [1,5]-on
s = 1:0.1:5
f = -0.8*s + 6.15
plot(s,f,x,y,'*','markersize',15)