△FEB≅△CNB.
What is length of BN¯¯¯¯¯¯ ?
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we know that
The CPCTC states that corresponding parts of congruent triangles are congruent
so
△FEB≅△CNB
that means
[tex]FE=CN\\FB=CB\\EB=NB[/tex]
we have
[tex]FE=6.1\ units\\FB=4.8\ units\\EB=3.8\ units[/tex]
therefore
[tex]BN=3.8\ units[/tex]
the answer is
the length of BN is [tex]3.8\ units[/tex]