Quadrants · Superchallenge problem

Three corners of a rectangle are $\left(-\dfrac{2}{3}, \dfrac{1}{2}\right)$, $\left(\dfrac{7}{6}, \dfrac{1}{2}\right)$ and $\left(\dfrac{7}{6}, -\dfrac{5}{4}\right)$. What is the area of the rectangle? Give your answer as a fraction in lowest terms.