document.write( "Question 1142489: Hi Please help me.
\n" ); document.write( "1. The depth d of a liquid in a bottle with a hole of area 0.5 cm2 in its side can be approximated by
\n" ); document.write( "d = 0.0034t2 − 0.52518t + 20,
\n" ); document.write( "where t is the time since a stopper was removed from the hole. When will the depth be 1 cm? Round to the nearest tenth of a second.\r
\n" ); document.write( "\n" ); document.write( "2. A small pipe can fill a tank in 9 min more time than it takes a larger pipe to fill the same tank. Working together, the pipes can fill the tank in 6 min. How long would it take each pipe, working alone, to fill the tank?\r
\n" ); document.write( "\n" ); document.write( "3. A car travels 238 mi. A second car, traveling 9 mph faster than the first car, makes the same trip in 1 h less time. Find the speed of each car.\r
\n" ); document.write( "\n" ); document.write( "4. A homeowner hires a mason to lay a brick border around a rectangular patio that measures 8 ft by 10 ft. If the total area of the patio and border is 168 ft2, what is the width of the border?
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Algebra.Com's Answer #763198 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
1. The depth d of a liquid in a bottle with a hole of area 0.5 cm2 in its side can be approximated by
\n" ); document.write( "d = 0.0034t^2 − 0.52518t + 20, where t is the time since a stopper was removed from the hole. When will the depth be 1 cm? Round to the nearest tenth of a second.
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\n" ); document.write( "d = 0.0034t^2 − 0.52518t + 20 = 1
\n" ); document.write( "0.0034t^2 − 0.52518t + 19 = 0
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\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"0.0034x%5E2%2B-0.52518x%2B19+=+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=%28-0.52518%29%5E2-4%2A0.0034%2A19=0.0174140324\".
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\n" ); document.write( " Discriminant d=0.0174140324 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--0.52518%2B-sqrt%28+0.0174140324+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-0.52518%29%2Bsqrt%28+0.0174140324+%29%29%2F2%5C0.0034+=+96.6385644909046\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-0.52518%29-sqrt%28+0.0174140324+%29%29%2F2%5C0.0034+=+57.8261413914483\"
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\n" ); document.write( " Quadratic expression \"0.0034x%5E2%2B-0.52518x%2B19\" can be factored:
\n" ); document.write( " \"0.0034x%5E2%2B-0.52518x%2B19+=+%28x-96.6385644909046%29%2A%28x-57.8261413914483%29\"
\n" ); document.write( " Again, the answer is: 96.6385644909046, 57.8261413914483.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+0.0034%2Ax%5E2%2B-0.52518%2Ax%2B19+%29\"

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\n" ); document.write( "t = the smaller solution.
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