least square solution of linear system of equations

i have homework about least square solution that i have a linear system of equation

x1 + x2 + x3 = 4

-2x1 + 2x2 + x3 = 6

x1 + x2 - 2x3 = 6

anyone know how to find least square solution of the least square solution in matlab?

(answer output must be in vector form(x1,x2,x3))

Answer 1

[Johannes Hougaard]

Although you should do your homework yourself I think I can help you : )

This problem could be solved with the backslash operator (or mldivide)

X = [1 1 1
    -2 2 1
    1 1 -2]; % These are the coefficients from your linear system
Y = [4
    6 
    6]; % these are the responses from your linear system
P = X\Y; % and P' would be your [x1,x2,x3]