<PRE><B>Question 280874</B>
the distance of an object traveling is a straight line is s=t^2-8t where s is in feet and t is in seconds.  how long will take for an object to travel 9ft?

s=9

9=t^2-8t

t^2-8t-9=0

t^2-9t+t-9=0

t(t-9)+1(t-9)=0

(t-9)(t+1)=0

t=9 or -1

After 9 seconds   since t=-1 is not possible




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