Answer:
The length of KM is
units.
Step-by-step explanation:
Given the statement: KLMN is a trapezoid, ∠N= ∠KML, FD=8,
, F∈ KL, D∈ MN , ME ⊥ KN KF=FL, MD=DN,
.
From the given information it is noticed that the point F and D are midpoints of KL and MN respectively.
The height of the trapezoid is
.
Midsegment is a line segment which connects the midpoints of not parallel sides. The length of midsegment of average of parallel lines.
Since
, therefore LM is 3x and KN is 5x.
![\frac{3x+5x}{2}=8](https://tex.z-dn.net/?f=%5Cfrac%7B3x%2B5x%7D%7B2%7D%3D8)
![\frac{8x}{2}=8](https://tex.z-dn.net/?f=%5Cfrac%7B8x%7D%7B2%7D%3D8)
![x=2](https://tex.z-dn.net/?f=x%3D2)
Therefore the length of LM is 6 and length of KN is 10.
Draw perpendicular on KN form L and M.
![KN=KA+AE+EN](https://tex.z-dn.net/?f=KN%3DKA%2BAE%2BEN)
(KA=EN, isosceles trapezoid) ![EN=2](https://tex.z-dn.net/?f=EN%3D2)
![KE=KN-EN=10-2=8](https://tex.z-dn.net/?f=KE%3DKN-EN%3D10-2%3D8)
Therefore the length of KE is 8.
Use Pythagoras theorem is triangle EKM.
![Hypotenuse^2=base^2+perpendicular^2](https://tex.z-dn.net/?f=Hypotenuse%5E2%3Dbase%5E2%2Bperpendicular%5E2)
![(KM)^2=(KE)^2+(ME)^2](https://tex.z-dn.net/?f=%28KM%29%5E2%3D%28KE%29%5E2%2B%28ME%29%5E2)
![(KM)^2=(8)^2+(3\sqrt{5})^2](https://tex.z-dn.net/?f=%28KM%29%5E2%3D%288%29%5E2%2B%283%5Csqrt%7B5%7D%29%5E2)
![KM^2=64+9(5)](https://tex.z-dn.net/?f=KM%5E2%3D64%2B9%285%29)
![KM=\sqrt{109}](https://tex.z-dn.net/?f=KM%3D%5Csqrt%7B109%7D)
Therefore the length of KM is
units.