a) The quadratic equation is:

which is of the form

Let's analyze the radicand:

The radicand is zero: this means that the equation has 2 coincident solutions.
We can find them by using the formula:

So, the solution is x=-0.2 with multiplicity 2.
b) The equation is

Note that the radicand is zero again, as before:

So we have two coincident solutions as before. We can find them using the same formula:

So, the solution is x=0.5 with multiplicity 2.