import math
def quadratic_equation(a, b, c):
    t = math.sqrt(b * b - 4 * a * c)
    m= (-b + t) / (2 * a)

    n=( -b - t )/ (2 * a)

    return m,n

print quadratic_equation(2, 3, 0)
print quadratic_equation(1, -6, 5)

# n=( -b - t )/ (2 * a) 和return m,n 缩进多了一个空格

注意缩进