Determine the value(s) of k for which the expression is a perfect square trinomial.
x^2+kx+36

If the quadratic is a perfect square, then there has to be a way to write the quadratic as , where is a root of the equation. Expanding it out, we see that



Now let's compare this form to the one that we were given. Since matches up with , has to equal either or . So, since in the original equation matches up with in the equation we found, and

or