Roof pitch percentage:
\[ \text{pitch(%)} = \frac{x}{12} \times 100\% \]
Roof pitch in degrees:
\[ \text{pitch(deg)} = \arctan\left(\text{pitch(%)}\right) \]
Total area of the roof:
\[ \text{roof area} = \frac{\text{base area}}{\cos\left(\text{pitch(deg)}\right)} \]