The area formula for a trapezoid can be written as ¹/₂(base₁+base₂)*h.
The average of the bases, ¹/₂(base1+base2), is called the median of the trapezoid.
So the area can be seen as the median*h, a much simpler rectangular formula.
We will transform by rotation the trapezoid into a rectangle by using the rotation slider.
Adjust the width of the trapezoid by dragging on the corners; this app works when the base2 angles are acute.
Adjust the height of the trapezoid by using the slider.