What are all operations with fractions that require a common denominator

Adding Fractions: If the denominators are not the same, you must find the common denominator by finding the least common multiple (LCM). Subtracting Fractions: If the denominators are not the same, you must find the common denominator by finding the least common multiple (LCM).

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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