If (t-8) is a factor of t^2 - kt - 48, then k =
a. -6
b. -2
c. 2
d. 6
e. 14
answer is C
could someone explain this? I do not like the explanation in the book and having hard time to understand it. Thanks
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deagez
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I guess what brought me to start the problem off this way, is the 8 in (t-8),,,so my next thought is what multiplied by 8 would be a negative 48?
6 right? so that is how I decided to do (t-8)(t+6) and see what the middle factor "k" would be
6 right? so that is how I decided to do (t-8)(t+6) and see what the middle factor "k" would be
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tohellandback
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t-8 is a factor
just put t=8 in the eq and it should be 0
t^2 - kt - 48
8^2-k*8-48=0
16-8k=0
k=2
just put t=8 in the eq and it should be 0
t^2 - kt - 48
8^2-k*8-48=0
16-8k=0
k=2
The powers of two are bloody impolite!!
