In the box below, the trapezoid should have a base 1 ([math]b_1[/math]) of 2 units, a base 2 ([math]b_2[/math]) of 6 units, and a height (h) of 3. If it does not, move the blue vertices to create a trapezoid with those dimensions. Then, slide the slider.
The slider took a copy of the original trapezoid, flipped it, and connected it to the original trapezoid. What shape do the two trapezoids make?
How many units is the base of the new shape?
How many units is the height of the new shape?
What is the area of the new shape?
You found the area of the new shape, which is made up of two identical trapezoids. What is the area of one of the trapezoids?
Great work! You found the area of a trapezoid! Let's make a new one and try it again. Move the blue vertices to create a trapezoid where [math]b_1=4[/math], [math]b_2=2[/math], and [math]h=5[/math]. Once you have made the trapezoid with the given dimensions, slide the slider.
What is the base of the parallelogram?
What is the height of the parallelogram?
What is the area of the parallelogram?
What is the area of the trapezoid?
Nice! Let's try another one. Move the blue vertices to create a trapezoid where [math]b_1=9[/math], [math]b_2=3[/math], and [math]h=6[/math]. Once you have made the trapezoid with the given dimensions, slide the slider.
What is the area of the parallelogram?
What is the area of the trapezoid?
Superb! Let's try another one. Move the blue vertices to create a trapezoid where [math]b_1=3[/math], [math]b_2=4[/math], and [math]h=5[/math]. Once you have made the trapezoid with the given dimensions, slide the slider.
What is the area of the parallelogram?
What is the area of the trapezoid?
Amazing! Let's try one more. Move the blue vertices to create a trapezoid where [math]b_1=10[/math], [math]b_2=6[/math], and [math]h=7[/math]. Once you have made the trapezoid with the given dimensions, slide the slider.
What is the area of the trapezoid?
Now that you've had some practice, describe the steps it takes to find the area of a trapezoid.
What is the greatest area you can make with a right trapezoid (a trapezoid with two right angles) that has a perimeter of 46 units?