Divide a line segment of length 14 cm internally in the ratio 2 : 5. Also, justify your construction.


Steps of Construction:


1. Draw any ray AX, making an acute angle with AB.


2. Locate 7 points A1, A2, A3, A4, A5, A6 and A7 on AX so that AA1 = A1A2 = A2A3 = A3A4 = A4A5 = A5A6= A6A7


3. Join BA7.


4.Through the point A2, draw a line parallel to A7B at A2 intersecting AB at the point C . Then, AC : CB = 2 : 5.


Justification


Since A2C is parallel to A7B, therefore,


AA5/A5A7 (By the Basic Proportionality Theorem) = AC/CB


AA By construction, AA4/A4A7 Therefore, AC/CB = 2/5


This shows that C divides AB in the ratio 2 : 5.


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