If BC is 1
CD is 2
DA is 3
AB is 4,
what is EF?

The length of the side EF will be 1 unit, approximately.
The complete figure is attached below.
It deals with the size of geometry, region, and density of the different forms both 2D and 3D.
The figure is given below.
The length of EF will be
EF = CF – CE
Then the value of CF will be
CF = BC × cos 30
CF = 2 × 0.866
CF = 1.732
Then the value of CE will be
CE = BC × cos 42
CE = 1 × 0.743
CE = 0.743
Then we have
EF = 1.732 – 0.743
EF = 0.989 ≈ 1
More about the geometry link is given below.
https://brainly.com/question/7558603
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