Use back substitution in MATLAB $($see canvas$)$ to solve the linear system $Ax=b$ with

$A=([1,2,3,4,5],[0,6,7,8,9],[0,0,10,11,12],[0,0,0,13,14],[0,0,0,0,15]),b=([-0\mathrm{.}2],[-15\mathrm{.}6],[4\mathrm{.}6],[5\mathrm{.}4],[3])$

Write a script to print the solution $x,$ compute and print the residual $r=Ax-b($the entries should be zero or very small, right?$),$ and the norm of the residual norm$(r).$