document.write( "Question 466674: Help...spent two nights on these and cannot solve.
\n" ); document.write( "A) During the first part of a trip, a canoeist travels 63 miles at a certain speed. The canoeist travels 10 miles on the second part of a trip at a speed of 5 mph slower. The total time for the trip is 4 hours. What was the speed on each part of the trip?
\n" ); document.write( "B) Write a quadratic equation having the given numbers as a solution; -6,-2.
\n" ); document.write( "C) Write a quadratic equation in the variable x having the given numbers as solutions. Type the equation in standard form ax^2+bx+c=0; -sqrt 5, 3 sqrt 5.
\n" ); document.write( "Thank you so much for your help!!!
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Algebra.Com's Answer #319955 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
A) During the first part of a trip, a canoeist travels 63 miles at a certain speed. The canoeist travels 10 miles on the second part of a trip at a speed of 5 mph slower. The total time for the trip is 4 hours. What was the speed on each part of the trip?
\n" ); document.write( "r = the \"certain speed\"
\n" ); document.write( "t = d/r = 63/r + 10/(r-5) = 4
\n" ); document.write( "Multiply thru by r*(r-5)
\n" ); document.write( "63(r-5) + 10r = 4r(r-5) = 4r^2 - 20r
\n" ); document.write( "63r-315 + 10r = 4r^2 - 20r
\n" ); document.write( "\"4r%5E2+-+93r+%2B+315+=+0\"
\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 \"4x%5E2%2B-93x%2B315+=+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=%28-93%29%5E2-4%2A4%2A315=3609\".
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\n" ); document.write( " Discriminant d=3609 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--93%2B-sqrt%28+3609+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-93%29%2Bsqrt%28+3609+%29%29%2F2%5C4+=+19.1343691479378\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-93%29-sqrt%28+3609+%29%29%2F2%5C4+=+4.11563085206221\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"4x%5E2%2B-93x%2B315\" can be factored:
\n" ); document.write( " \"4x%5E2%2B-93x%2B315+=+%28x-19.1343691479378%29%2A%28x-4.11563085206221%29\"
\n" ); document.write( " Again, the answer is: 19.1343691479378, 4.11563085206221.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-93%2Ax%2B315+%29\"

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\n" ); document.write( "r = x
\n" ); document.write( "Ignore the answer that's less than 5.
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\n" ); document.write( "B) Write a quadratic equation having the given numbers as a solution; -6,-2.
\n" ); document.write( "(x+6)*(x+2) = 0
\n" ); document.write( "\"x%5E2+%2B+8x+%2B+16+=+0\"
\n" ); document.write( "------------------
\n" ); document.write( "C) Write a quadratic equation in the variable x having the given numbers as solutions. Type the equation in standard form ax^2+bx+c=0; -sqrt 5, 3 sqrt 5.
\n" ); document.write( "\"%28x+%2B+sqrt%285%29%29%2A%28x+-+3sqrt%285%29%29+=+0\"
\n" ); document.write( "\"x%5E2+-+2x%2Asqrt%285%29+-+15+=+0\"
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