#coding=utf-8
import sympy
# 一元方程
# x=sympy.symbols('x')
# a=sympy.solve([x+(1/5)*x-240],[x])
# print(a)
# 二元方程
# x,y = sympy.symbols("x y")
# a = sympy.solve([3*x -2*y-3,x+2*y-5],[x,y])
# print(a)
# x,y = sympy.symbols("x y")
# a = sympy.solve([x + y - 0.2,x + 3*y -1],[x,y])
# x = a[x]
# y = a[y]
# re = x**2+4*x*y +4*y**2
# print(re)