The answer is 12 including both sides and angles.
When you cut a square piece of paper from one point to the opposite point it should make two triangles.
Thus each triangle has 3 sides and 3 angles so two triangles has 6 angles and 6 sides
So 12, sides and angles added together.
Decimal form: 4.05, 0.5
Exact form: 9/2, 1/2
The area of a trapezoid with base lengths 7 in and 19 in is given by
A = (1/2)(b1 + b2)h
A = (1/2)(7 +19)·7 = 91
The appropriate choice is
D. 91 in²
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It can also be figured by adding the area of the 7 in square (49 in²) to the area of the 7×12 in right triangle (42 in²).