Answer: 96 square units (choice B)
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Step-by-step explanation:
Triangle OBI has a base of OI = 12 units along the horizontal component, and CB = 8 is the vertical component or the height.
area of triangle OBI = 0.5*base*height
area of triangle OBI = 0.5*12*8
area of triangle OBI = 48 square units
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Now find the area of the trapezoid GNIO. The two horizontal components are the parallel bases GN = 4 and OI = 12. The height of this trapezoid is the vertical component CD = 6, where point D is added on to be at location (0,-6) on the graph.
area of trapezoid = (height*(base1+base2))/2
area of trapezoid GNIO = 6*(4+12)/2
area of trapezoid GNIO = 48
Coincidentally, the triangle and trapezoid both have the same area
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The last thing to do is add the two areas of the triangle and trapezoid
total area = (area of triangle OBI) + (area of trapezoid GNIO)
total area = (48) + (48)
total area = 96 square units