a.What is the length of A’A?
b.What is the length of B’B
Both in units

Answer:
A'A = 18 units, B'B = 9 units
Step-by-step explanation:
Δ ACB and Δ A'CB' are similar triangles, thus the ratios of corresponding sides are equal, that is
[tex]\frac{AC}{A'C}[/tex] = [tex]\frac{AB}{A'B'}[/tex] , substitute values
[tex]\frac{AC}{12}[/tex] = [tex]\frac{20}{8}[/tex] ( cross- multiply )
8AC = 240 ( divide both sides by 8 )
AC = 30
Thus A'A = AC - A'C = 30 - 12 = 18 units
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and
[tex]\frac{CB}{CB'}[/tex] = [tex]\frac{AB}{A'B'}[/tex] , that is
[tex]\frac{CB}{6}[/tex] = [tex]\frac{20}{8}[/tex] ( cross- multiply )
8CB = 120 ( divide both sides by 8 )
CB = 15
Thus
B'B = CB - CB' = 15 - 6 = 9 units