Q$3$

$(10$ pts$.)$ Use the Gauss$-$Seidel method to solve the following system until the approximate relative

error falls below $lo{n}_A=\mathrm{.}0005.$ If necessary, rearrange the equations to achieve convergence.

$-3x_1+x_2+12x_3=50$

$6x_1-x_2-x_3=3$

$6x_1+9x_2+x_3=40$

a$)$ using a built$-$in function in matlab $($linsolve$)$ or python $($numpy$.$linalg.solve$)$

b$)$ using a python or matlab script of Gauss$-$Seidel method that you write.

c$)$ what goes wrong, if anything, if the equations are not reordered?

Solve it by hand then write me a MATLAB code