Conic Sections · Hard problem

Convert $9x^2 - 16y^2 - 90x - 32y + 65 = 0$ to the standard form of a hyperbola, $\dfrac{(x-h)^2}{a^2} - \dfrac{(y-k)^2}{b^2} = 1$. Find $a^2 + b^2$.