in the adjoining figure ABC is a triangle and D is any point in its interior. show that (BD+DC) < (AB+AC).
Answers
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in the adjoining figure ABC is a triangle and D is any point in its interior. show that (BD+DC) < (AB+AC).
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Produce BD to meed AC at E.
We know that in a triangle, the sum of any two sides is always greater than the third side,
In ∆ABE,we have
AB + AE > BE ⇒ AB + AE > BD + DE.⠀⠀...(i)
In ∆CDE,we have
DE + EC > DC.⠀⠀⠀⠀..(ii)
From (i) and (ii), we get
AB + AE + DE + EC > BD + DE + DC
⇒AB + (AE + EC) > BD + DC
⇒(AB + AC) > (BD + DC).
Hence,(BD + DC) < (AB + AC).
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Question - the adjoining figure ABC is a triangle and D is any point in its interior. show that (BD+DC) < (AB+AC).
Solution - Produce BD to meed AC at E.
We know that in a triangle, the sum of any two sides is always greater than the third side,
In ∆ABE,we have
AB + AE > BE ⇒ AB + AE > BD + DE.⠀⠀...(i)
In ∆CDE,we have
DE + EC > DC.⠀⠀⠀⠀..(ii)
From (i) and (ii), we get
AB + AE + DE + EC > BD + DE + DC
⇒AB + (AE + EC) > BD + DC
⇒(AB + AC) > (BD + DC).
Hence,(BD + DC) < (AB + AC)...
hope it helps ❣️