This is a trigonometry question .

AB ≈ 5.6 cm

Step-by-step explanation:

Using the cosine ratio in the right triangle

cos62° = = = ( multiply both sides by 12 )

12 × cos62° = AB , thus

AB ≈ 5.6 cm ( to 1 dec. place )

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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