Question

In the figure, AB ll DE and BD ll EF. PROVE : DC SQUARE = CF x AC​

Answer 1

Answer:

DC² = CF × AC

Step-by-step explanation:

Given---> AB || DE and BD || EF in ΔABC

To prove ---> DC² = CF × AC

Proof ---> In Δ ABC and Δ CDE

AB || DE

So , ΔABC ~ ΔCDE

So ratio of corresponding sides of Δ ABC and ΔCDE are same

So

DC / AC = CE / BC --------------(1)

In Δ CFE and Δ CDB

FE || DB

So , Δ CFE ~ Δ CDB

So ratio of corresponding sides of Δ CFE

and Δ CDB are same

So

CF / DC = CE / BC -----------------(2)

By relation (1) and (2) we have

DC / AC = CF / DC

=> DC² = AC × CF

Answer 2

Step-by-step explanation:

See the attachment please.......