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In a DeltaABC it is given that angleA:an...

In a `DeltaABC` it is given that `angleA:angleB:angleC=3:2:1andangleACD=90^(@)`
If BC is produced to E then `angleECD=?`

A

`60^(@)`

B

`50^(@)`

C

`40^(@)`

D

`25^(@)`

Text Solution

Verified by Experts

The correct Answer is:
A
`angleA+angleB+angleC=180^(@)implies3x+2x+x=180`
`implies6x=180impliesx=30`.
`:.angleA=90^(@),angleB=60^(@)andangleC=30^(@)`.
`angleACE=angleA+angleBimplies90^(@)+angleECD=90^(@)+60^(@)impliesECD=60^(@)`.
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