To find the area of a quadrilateral, we need more information than just two side lengths (12 in. and 16 in.). The area can depend on the shape of the quadrilateral.
If we assume that the quadrilateral is a rectangle (where the lengths of opposite sides are equal and all angles are right angles), the area can be calculated using the formula:
\[ \text{Area} = \text{length} \times \text{width} \]
For a rectangle with sides of 12 inches and 16 inches:
\[ \text{Area} = 12 , \text{in.} \times 16 , \text{in.} = 192 , \text{in}^2 \]
If the quadrilateral is a different shape (like a trapezoid, parallelogram, etc.), please provide more details about the shape or any angles, and I can help you calculate the area accordingly.