Answer: Choice D) 499.2 cm^2
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Step-by-step explanation:
There are 8 identical triangles shown here (ignore the dashed vertical line). We know they are identical because of the phrasing "same size and same shape". In other words, the triangles are congruent.
Each triangle has base 12 cm and height 10.4 cm
So the area of each triangle is base*height/2 = 12*10.4/2 = 62.4 square cm.
In total, all 8 triangles combine to an area of 8*62.4 = 499.2 square cm which points us to choice D