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Known: as shown in the figure, in rectangular ABCD, points E and F are on the edge of AD, CE and CF intersect with BD at points m, N, AE = EF = FD = 4cm, ab = 16cm, respectively, to find the length of Mn
BD=20
△DFN∽△BCN
DN:NB=DF:BC=1:3
DN:DB=1:4
DN=5
△EMD∽△CMB
DM:MB=DE:BC=2:3
DM:DB=2:5
DM=8
MN=DM-DN=8-5=3
For the quadrilateral ABCD, ab = CD, e and F are the midpoint of BC and ad respectively, the extension lines of Ba and EF intersect at m, the extension lines of CD and EF intersect at n, and the verification ∠ ame = ∠ dne is made
First, use the parallel line bisection theorem to find ab ∥ CD, and then the two lines are parallel, with the same angle!
RELATED INFORMATIONS
- 1. In the quadrilateral ABCD, ab = CD, e and F are the midpoint of BC and ad. the extension lines of Ba and EF intersect at m, the extension lines of CD and EF intersect at n, proving that angle ame is equal to angle dne
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