#範例5-13：用sympy解聯立方程式，求唯一解
from sympy import *
x1,x2,x3,x4 = symbols('x1 x2 x3 x4')
#注意：M矩陣的最右邊=y=轉換後座標
A = Matrix([
    [1,3,7,2,5],
    [0,1,2,-4,1],
    [0,0,1,6,9],
    [1,0,0,0,1]
    ])
ans = solve_linear_system(A, x1, x2, x3, x4)
print('X=', ans)