document.write( "Question 1101603: A particle moves along a horizontal line. Position function is s(t) for t is greater or equal to 0. Find the intervals of time when the particle is moving left and moving right.\r
\n" ); document.write( "\n" ); document.write( "s(t) = t^2 -16t +28\r
\n" ); document.write( "\n" ); document.write( "I got v(t) = 2t-16 so t= 8
\n" ); document.write( " a(t) = 2 but what is t for a(t)?
\n" ); document.write( "and how do you use a number line with that? \n" ); document.write( "

Algebra.Com's Answer #716199 by Boreal(15235) $\"\"$ $\"About$

You can put this solution on YOUR website!
the first derivative is 0 at t=8
\n" ); document.write( "Here is the graph.
\n" ); document.write( " $\"graph%28300%2C300%2C-5%2C15%2C-50%2C40%2Cx%5E2-16x%2B28%2C2x-16%29\"$
\n" ); document.write( "The particle is moving left from [0, 8). and it is moving right from (8, oo). ANSWER
\n" ); document.write( "At t=8 the instantaneous velocity is 0.
\n" ); document.write( "Can visualize moving left as down in this instance and moving right as up. The x-intercepts are only where the particle is at 0, which is not a consideration here. \n" ); document.write( "

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