The equation of the line is:
\[ \frac{x}{7\sqrt{3a}} + \frac{y}{b} = 4. \]
Rewriting:
\[ b \cdot x + 7\sqrt{3a} \cdot y = 28\sqrt{3ab}. \]
To find the intercepts:
1. When \( x = 0 \), \( y = 4b \).
2. When \( y = 0 \), \( x = 28\sqrt{3a} \).
The lines \( x = 0 \) and \( y = 0 \), together with \( \frac{x}{7\sqrt{3a}} + \frac{y}{b} = 4 \), form a triangle with vertices:
\[ (0, 0), \quad (28\sqrt{3a}, 0), \quad (0, 4b). \]
The area of the triangle is:
\[ \text{Area} = \frac{1}{2} \times \text{base} \times \text{height}, \]
where the base is \( 28\sqrt{3a} \) and the height is \( 4b \):
\[ \text{Area} = \frac{1}{2} \times (28\sqrt{3a}) \times (4b). \]
Simplify:
\[ \text{Area} = \frac{1}{2} \times 112\sqrt{3ab} = 56\sqrt{3ab}. \]
Thus, the area of the region is:
\[ 56\sqrt{3ab}. \]