document.write( "Question 1100705: A firework is launched off a building with an initial height of 152 ft, and an initial velocity off 481 ft/s. The firework will explode at 630 ft. How long after setting the firework off should the delay be set. Graph. \n" ); document.write( "
Algebra.Com's Answer #715279 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
630=-16t^2+481t+152
\n" ); document.write( "152-630=478
\n" ); document.write( "solve for t
\n" ); document.write( "t=1.02898316343029 =1.03
\n" ); document.write( "t= 29.0335168365697= 29.03
\n" ); document.write( "Unfortunately the graph doesn't show.
\n" ); document.write( "I am using a pluggable solver by another tutor
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-16x%5E2%2B481x%2B-478+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28481%29%5E2-4%2A-16%2A-478=200769\".
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\n" ); document.write( " Discriminant d=200769 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-481%2B-sqrt%28+200769+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28481%29%2Bsqrt%28+200769+%29%29%2F2%5C-16+=+1.02898316343029\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28481%29-sqrt%28+200769+%29%29%2F2%5C-16+=+29.0335168365697\"
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\n" ); document.write( " Quadratic expression \"-16x%5E2%2B481x%2B-478\" can be factored:
\n" ); document.write( " \"-16x%5E2%2B481x%2B-478+=+%28x-1.02898316343029%29%2A%28x-29.0335168365697%29\"
\n" ); document.write( " Again, the answer is: 1.02898316343029, 29.0335168365697.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-16%2Ax%5E2%2B481%2Ax%2B-478+%29\"

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