%% How to Plot 3 Lines

%% Consider the following linear system
disp('x + 2y = 1')
disp('2x + y = 2')
disp('3x - 3y = 3')

%% Define a range of x values
x = -10:10;

%% Solve for 
y1 = -.5*x + .5;
y2 = -2*x + 2;
y3 = 3*x - 3;

%% Plot the three lines in three colors
plot(x,y1,'r',x,y2,'b',x,y3,'g')