#!/usr/bin/python3
import numpy as np


def main():
	a=np.array([[1,1,1],
		   [0,2,5],
		   [2,5,-1]])
	print("Det=",np.linalg.det(a))
	ainv=np.linalg.inv(a)
	#b=np.array([[6],[-4],[27]])
	b=np.array([6,-4,27])
	b=b.reshape(3,1)
	#print(b)
	x=np.matmul(ainv,b)
	#print("x=",x)
	print(x)
	print("--------------------")
	y=np.linalg.solve(a,b)
	print(y)


if __name__=="__main__":
	main()