In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

The length of DE is 14 cm.

Step-by-step explanation:

Given in triangle ABC segment DE is parallel to the side AC . (The endpoints of segment DE lie on the sides AB and BC respectively). we have to find the length of DE.

Given lengths are AC=20cm, AB=17cm, and BD=11.9cm

In ΔBDE and ΔBAC

∠BDE=∠BAC       (∵Corresponding angles)

∠BED=∠BCA       (∵Corresponding angles)

By AA similarity rule, ΔBDE~ΔBAC

∴their corresponding sides are in proportion

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answer: all of the odd numbers were opened

the first person was the one that was opening all of the lockers. since one is odd, this causes all of the odd number lockers to be opened in the end.

ratio is 2 : 9

the answer is three

13.5 : 3