A) 11.5 km
B) 9.5 km
C) 9 km
D) 9.7 km

C) 9 km

Step-by-step explanation:

Area of parallelogram = 84.6 km²

base * height = 84.6

9.4 * height = 84.6

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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