Answer: 4 units
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Work Shown:
Start at point A' and count how many spaces it takes to get to E'. You should count out 6 spaces. This means A'E' = 6
Since A'E' is 6 units long, and the scale factor is 3/2 = 1.5, this means we can say
x = length of AE
y = length of A'E' = 6
x*1.5 = y
x*1.5 = 6
x = 6/1.5
x = 4
Segment AE is 4 units long