Neela's answer is excellent**.**

For the triangle (whose height is the breadth of rectangle) to be having the same area as the rectangle, the base has to be twice as long as the length of the rectangle.

[ Comparing the formula for area of rectangle (**length** x **breadth**) and area of triangle (**1/2 **x **base** x **height**), for these two expressions to be equal when the **breadth** of rectangle is equal to **height** of triangle, it follows that **base** has to be **2xlength** of rectangle ]