Answers

2014-11-24T15:42:04+05:30
D= b² - 4ac =0
  
[2(k-12)]
²  - 4×( k-12)×(2) =0 

4 ( k
² - 24k + 144 )  - 8k + 96 =0 

4k
²  - 96k + 576 - 8k + 96 = 0 

4k
²  - 104 k +672 = 0

k²  -2 6k +168 =0 

By factorising method
 
k
² - 14k - 12k +168 = 0 
 k×( k-14) -12× (k-14) =0 
(k-12)(k-14)=0 
k=12  or  k=14 

But k = 12 cannot satisfy the equation . So the value for k is 14.

K = 14.
0
thanxxx for advice . Please refresh the page and see it.
how? can u explain?
means
ok i understood
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