Answer:
16. 216 square inches
18. 252 square cm
Explanation:
16. The figure can be decomposed into a 12×17 rectangle and a triangle with base 16-12=4 and height 17-11=6.
Then the area is ...
rectangle area = 12×17 = 204
triangle area = (1/2)(4×6) = 12
total area = rectangle area + triangle area = 204 +12 = 216 . . . square inches
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18. The figure can be decomposed into a 12×12 square and a 18×6 rectangle. Then the total area is ...
area = 12×12 + 18×6 = 252 . . . square cm