The equation is
.
Subtract 4 from each side.
\

Compare the equation with
.
a = 1, b = 4 and c =
.
a) Now we can find discriminant value
\
(Substitute a = 1, b = 4 and c =
)

Product of same sings is positive.
\

b) The discriminant is positive, so the equation have two rational roots.
\c) Apply quadratic formula: 
(Replace
, a with 1, and b with 4)



The solutions are
.
The discriminant value is 20 and the equation have two irrational roots.
\The solutions are
.