import sympy as sym

# Defining symbols:

x, y, a, b, c = sym.symbols('x, y, a, b, c')

# Solving equation:

E1 = [a*x + b*y - c, x + y - 1]
E2 = sym.solve(E1, (x, y))
print('E2 =', E2)
print('x = ', E2[x])
print('y = ', E2[y])