Question 1019281
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See the lesson <A HREF=http://www.algebra.com/algebra/homework/Parallelograms/Three-parallel-lines-cut-off-proportional-segments-in-any-two-transverse-lines.lesson>Three parallel lines cut off proportional segments in any two transverse lines</A> in this site.


You will find the proof of this property there:


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If three parallel lines are intersected by two transverse lines,  then the ratio of the segment lengths they cut off 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;in one transverse line is equal to the ratio of the segment lengths they cut off in the second transverse line.