Using linprog but it's only returning 'Optimal solution found' with no feasible solution?

This is my first time using MATLAB and I'm so confused. This is my input:

f = [-4000 -5000];
A = [6 5; 
    4 6; 
    -6 -5; 
    -9 -5; 
    -1 0; 
    0 -1];
b = [500 400 -300 -200 0 0];
Aeq = [];
beq = [];
X = linprog(f,A,b,Aeq,beq)

Optimal solution found.

X = 2×1

62.5000 25.0000

As you can see, all I get in return is "Optimal solution found." Is there something I'm missing possibly? I feel like it should be easy, but like I said I've never used MATLAB.

[Bruno Luong]

You should explain why/what the result surprise you, don't let us guess.

Answer 1

[Bruno Luong]

It looks solution is correct to me.

Note that the Aeq = [] meaning you don"t supply equality constraint, so I need to check for inquelity constraints of the solution and the constraints are satisfied as showed here:

f = [-4000 -5000];
A = [6 5; 
    4 6; 
    -6 -5; 
    -9 -5; 
    -1 0; 
    0 -1];
b = [500 400 -300 -200 0 0];
Aeq = [];
beq = [];
X = linprog(f,A,b,Aeq,beq)

Optimal solution found.

X = 2×1

62.5000 25.0000

A*X-b(:)

ans = 6×1

0 0 -200.0000 -487.5000 -62.5000 -25.0000

all(A*X<=b(:))

ans = logical
   1