Answer
In Vastu the shape of the plot is very important. The rectangular and square shaped plot is the best plot for Vastu.
A chart is given below about shape of plot and their result;
Shape ----- Result
Square ----- Beneficial for Health and Wealth
Rectangular ----- Increasing Heath, Wealth and Wisdom
Circular ----- Not good
Hexagonal ----- Ashubha ( Not good )
Wheel Shaped ----- Sorrowful ( Kashtakarak )
Triangular ----- Harmful for land owner
Oval Shaped ----- Beneficial for religious work
Semi Circle ----- Harmful for land owner
Table shaped ----- Emptiness for plot owner.