Suppose A = |a b c| it's a matrix
|d e f|
|g h i|
and det(A) = 15. Using only a simple calculator,
find det(M) where M = | a b c |
|4d+a 4e+b 4f+c|
| g h i |

Question

Suppose A = |a b c| it's a matrix
                      |d e f|
                      |g h i|
 and det(A) = 15. Using only a simple calculator, 
find det(M) where M = |   a            b          c   |
                                      |4d+a    4e+b   4f+c|  
                                      |   g            h          i    |

anonymous · Answer

who ever want to help me, you can give me steps and I will do it
Thanks for everyone!

shubhamsrg · Answer

det(M)= 1/4 det(A) !

anonymous · Answer

ok why?

shubhamsrg · Answer

well the value of determinant dosent change when you add rows simply..
and when you multiply a determinant with some constant,,any row or column gets multiplied with that no..

shubhamsrg · Answer

i mean on transforming any row,,value of det( ) dosent change. 
hope i was clear enough.

anonymous · Answer

yea
So the answer is 15/4?

shubhamsrg · Answer

ohh am sorry,,i meant det(A) = 1/4 det(M)

shubhamsrg · Answer

ans in 60 then.

anonymous · Answer

15*4=60?

shubhamsrg · Answer

the very same..

anonymous · Answer

yea I didn't see ur answer! lol
Thank you so much
Can you help me with one more?

shubhamsrg · Answer

i dont know.. :P

anonymous · Answer

you don't know what?

anonymous · Answer

I'm just asking you if you can??

shubhamsrg · Answer

i dont know if i'd be able to help.. i'll have to see the ques first,,ofcorse..

anonymous · Answer

ok I will post it
as you know it will take time to write a matrix!