calibration and transform point in new location [closed]

edit

Hi. i using Qtcalib for calibration. it give me 3 Matrices now:

K 3*3  = intrinsic parameters
R 3*3 = rotation matrix 
T 1*3 = translation matrix

i have question now, i have a line with two point, after calibration i want to know where is my Line points location now ? how i calculate new point ? because i want two determine size of that line after calibrate, i want know real length of that line(you can use 2D or 3D ) please help me to know whats formula to calculate : using that 2 matrices

(Xnew,Ynew)= Function(K,R,T,x,y)