



 
Ashley, I remember the area of a trapezoid as
I can show you why this is true for one type of trapezoid and leave it to you to check for other trapezoids. Suppose I have a trapezoid where both base angles are acute. Let s_{1} and s_{2} be the lengths of the parallel sides with s_{1} ≥ s_{2}and d be the distance between the parallel sides. Construct a rectangle with base s_{1} and height d. The area of the trapezoid is the area of this rectangle minus the areas of the two triangles shaded orange in the diagram. That is
But s_{1}  s_{2} = x + y so
Penny  


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