The picture in the attached figure
we know that
surface area=2*area of the base+perimeter*height
area of the base=area of the triangle
area of the base=3*4/2----> 6 cm²
perimeter of the base=perimeter of triangle
perimeter=3+4+5----> 12 cm
height=x cm
surface area=2*6+12*x
surface area=204 cm²
12+12*x=204
12*x=204-12
12*x=192
x=192/12
x=16 cm
the answer is16 cm
Width = w
Length = 2w + 5/2
Perimeter = 2(Length + Width)
Perimeter = 2( w + 2w + 5/2)
Perimeter = 2(3w + 5/2)
Perimeter = 6w + 5
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Answer: The perimeter is 6w + 5 (Answer D)
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