Answer:
11 units
Explanation:
The height of a trapezoid is the distance between the parallel bases.
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Here, one base lies on the horizontal line y=5, and the other lies on the horizontal line y = -6. The distance between them is ...
5 -(-6) = 5 +6 = 11
You can also find this distance by counting the grid squares between the two parallel lines.
The height of the trapezoid is 11 units.
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Additional comment
The base lengths are ...
AB = 2 -(-5) = 7
CD = 8 -(-7) = 15
The area is 1/2(b1 +b2)h = (1/2)(7 +15)(11) = 121 square units.