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In a DeltaABC,"if "angleA-angleB=42^(@)a...

In a `DeltaABC,"if "angleA-angleB=42^(@)andangleB-angleC=21^(@)" then "angleB=?`

A

`32^(@)`

B

`63^(@)`

C

`53^(@)`

D

`95^(@)`

Text Solution

Verified by Experts

The correct Answer is:
C
`angleA=angleB+42^(@)andangleC=(angleB-21^(@))`.
`A+B+C=180^(@)implies(B+42)+B+(B-21)=180`
`implies3B=159impliesB=63^(@)`
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