clf;
x1=[-4:.05:-2];
x2=[-2:.05: 1];
x3=[ 1:.05: 5];

y1=   x1 + 3;
y2=-2*x2 - 3;
y3=5*x3/4 - 25/4;

plot(x1,y1);
hold on;
plot(x2,y2);
hold on;
plot(x3,y3);

%plot([-4], [-1], 'o', 'MarkerEdgeColor', [0 0 0], 'MarkerFaceColor', [0 0 0]);
%hold on;
%plot([-2], [1], 'o', 'MarkerEdgeColor', [0 0 0], 'MarkerFaceColor', [1 1 1]);
%hold on;


xmin=-5;
xmax= 6;
ymin=-6;
ymax= 3;
axis([xmin xmax ymin ymax]);
h1=line([xmin xmax], [0 0]);
set(h1, 'LineStyle', '--');
h2=line([0 0], [ymin ymax]);
set(h2, 'LineStyle', '--');

set(gca, 'XTick', [xmin:1:xmax])
set(gca, 'YTick', [ymin:1:ymax])

%xlabel('x');
%ylabel('f(x)');
set(gcf, 'PaperPositionMode', 'Manual');
set(gcf, 'PaperPosition', [0 0 6 1.5])
print -depsc exam_01_fig_02

