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If one root of the equation x^(2)+ax+8=0...

If one root of the equation `x^(2)+ax+8=0` is 4 while the equation `x^(2)+ax+b=0` has equal roots, find b.

A

8

B

`16`

C

`24`

D

32

Text Solution

Verified by Experts

The correct Answer is:
B
Since 2 is only even prime.
Therefore we have
`2^(2)+lamda.2+12=0`
`implieslamda=8`
`:.x^(2)+lamdax+mu=0`
`impliesx^(2)+8x+mu=0`….i
But Eq. (i) has equal roots.
`:.D=0`
`implies 8^(2)-4.1=mu=0`
`impliesmu=16`
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