Answer: 20 square units
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Work Shown:
A = h*(b1+b2)/2 .... area of trapezoid formula
A = 4*(7+3)/2
A = 4*(10)/2
A = 40/2
A = 20 square units
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notes:
- The bases b1 and b2 are parallel to one another.
- b1 = 7 is the longer horizontal base at the bottom. It spans from x = 1 to x = 8, so it's 8-1 = 7 units long.
- b2 = 3 is the shorter horizontal base up top. It spans from x = 2 to x = 5, so it's a distance of 3 units.
- h = 4 is the height. We can count out 4 spaces when going one base to the other, or we can note that the y coordinates subtract to 4 (ie 5-1 = 4)
- The base and height are always perpendicular to one another.
- As an alternative way to solve, you can break the figure into 2 triangles and a rectangle in between. Find the area of each piece, and then add those areas up to get the final answer.
