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In a triangle ABC, a=4, b=3 ,angleA=60^(...

In a triangle ABC, a=4, b=3 `,angleA=60^(@)`, then c is the root of the equation

A

`c^(2) -3c-7=0`

B

`c^(2) +3c+7=0`

C

`c^(2) -3c+7=0`

D

`c^(2) +3c-7=0`

Text Solution

Verified by Experts

We have, a= 4, b = 3 and `angleA= 60°`
`thereforecosA=(b^(2)+c^(2)-a^(2))/(2bc)`
`rArrcos60^(@)=(9+c^(2)-16)/(6c)rArrc^(2)-3c-7=0`
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OBJECTIVE RD SHARMA ENGLISH-PROPERTIES OF TRIANGLES AND CIRCLES CONNECTED WITH THEM-Chapter Test
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