document.write( "Question 1176831: a) a baseball player hit a very high pop-up ball. H is the height in meters given by h(t) = 1+30t-5t^2 and t is the time in seconds. What height does this ball not reach?
\n" ); document.write( "b)if it is caught at the height it was hit, how long is it in the air. Round off to one decimal place.\r
\n" ); document.write( "\n" ); document.write( "I'm quite confused on how I can solve these, as I did try using the quadratic equation and it didn't work. \n" ); document.write( "

Algebra.Com's Answer #804655 by Boreal(15235) $\"\"$ $\"About$

You can put this solution on YOUR website!
I'm assuming that the first part is what height does it reach. What it does not reach is everything else.
\n" ); document.write( "h(t)=-5t^2+30t+1
\n" ); document.write( "vertex is at x=-b/2a or -30/-10 or at 3 seconds for t
\n" ); document.write( "h(3)=-45+90+1 or 46 m height reached.
\n" ); document.write( "set that equation equal to 1
\n" ); document.write( "there are two places where h(t)=1, at the bat and when caught.
\n" ); document.write( "so h(t)=-5t^2+30t=-5t(t-6)=0
\n" ); document.write( "t=6.0 seconds, twice the time to get to the vertex, since this is symmetric at h(t)=1 m
\n" ); document.write( " $\"graph%28300%2C300%2C-5%2C10%2C-10%2C50%2C1%2B30x-5x%5E2%2C46%2C1%29\"$ \n" ); document.write( "

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