Discriminant Problem |2|
~~~~~~~~~~~~~~~~~~~~~~~~

Ozi wants to help his sister with her math homework, which is about
determinig whether a given quadratic equation has real roots or not.

Remember that a given quadratic equation :math:`ax^2 + bx + c` has real
roots if the discriminant is greater than or equal to 0, where the
discriminant is defined as follows:

.. math::  \Delta = b^2 - 4ac 

.

Write a function called *has_real_roots* that takes three integers as
the coefficients of the equation and returns ``True`` if this equation
has real roots and ``False`` if not.

.. container:: sampleio

   Sample I/O:

.. |2| image:: ../../figures/difficulty_one.png
   :class: difficulty

.. code:: default

   >>> has_real_roots(1, -4, 4)
   True

   >>> has_real_roots(1, -2, 4)
   False

.. raw:: html

   <button type="button" class="collapsible" onclick="toggle()">

Show the Answer

.. raw:: html

   </button>

.. raw:: html

   <div class="hiddenanswer">

.. code:: python

   def has_real_roots(a, b, c):
       delta = b**2 - 4*a*c
       return delta >= 0

.. raw:: html

   </div>