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alex.gellatly
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If (t-8) is a factor of t^2-kt-48, then k=
-6
-2
2
6
14
The OA is C. However I got B. Although I understand the Official Guide's way of solving it, I solved it in the following manner and got a different answer:
t^2-kt-48 then it follows that
(t-8)(t+6) =0 (Because -8*6=-48) Therefore;
k must be the sum of -8 and 6, which is -2 option B. Can anyone tell me where I went wrong? Thanks
The Official Guide solves it by plugging 8 in for t and solving the equation. Again, I understand why/how this works, but I don't understand why/how my approach is wrong.
Thanks
-6
-2
2
6
14
The OA is C. However I got B. Although I understand the Official Guide's way of solving it, I solved it in the following manner and got a different answer:
t^2-kt-48 then it follows that
(t-8)(t+6) =0 (Because -8*6=-48) Therefore;
k must be the sum of -8 and 6, which is -2 option B. Can anyone tell me where I went wrong? Thanks
The Official Guide solves it by plugging 8 in for t and solving the equation. Again, I understand why/how this works, but I don't understand why/how my approach is wrong.
Thanks
A useful website I found that has every quant OG video explanation:
https://www.beatthegmat.com/useful-websi ... tml#475231
https://www.beatthegmat.com/useful-websi ... tml#475231
