Visualizing 2d rotation plot

I did this rotation sometime ago and I want to visualize it on the plot to confirm my rotation. Any help?

I USED THE CODE BELOW

target_x = 27.000;

target_y = 16.000;

start_x = 24.000;

start_y = 16.000;

p = [target_x target_y]';

rotPt = [start_x start_y]';

theta = pi/4 ;

R = [cos(theta) -sin(theta); sin(theta) cos(theta)];

pTmp = p - rotPt;

pRotTmp = R * pTmp;

pRot = pRotTmp + rotPt;