document.write( "Question 206251: Wondering if I am on the right track. I need to determine a quadratic equation to solve the problem and also solve the problem. My word question is as follows: The perimeter of a rectangle is 34 cm and the diagonal is 13 cm. Determine the lengths of the side of the rectangle.\r
\n" ); document.write( "\n" ); document.write( "I am setting up my equation as follows:
\n" ); document.write( " 2x + 2y = 34
\n" ); document.write( " x^2 + y^2 = 169\r
\n" ); document.write( "\n" ); document.write( "I then determine (x) by the following equation:
\n" ); document.write( " 2x + 2y = 34
\n" ); document.write( " 2x = 34 - 2y
\n" ); document.write( " x = 17 - y\r
\n" ); document.write( "\n" ); document.write( "Then I am taking the following equation to come up with a quadratic equation:
\n" ); document.write( " (17-y)^2 + y^2 = 169
\n" ); document.write( " 189 - 34y + y^2 + y^2 = 169
\n" ); document.write( " 2y^2 - 34y = -20
\n" ); document.write( " 2y^2 - 34y + 20 = 0\r
\n" ); document.write( "\n" ); document.write( "Then my final answer (?) after calculating the quadratic equation is:\r
\n" ); document.write( "\n" ); document.write( " x = 34 + or - 498 / 4
\n" ); document.write( " x = 133 and x = 116\r
\n" ); document.write( "\n" ); document.write( "My question is, am I doing this correctly or am I missing a step?\r
\n" ); document.write( "\n" ); document.write( "Your input would be greatly appreciated.\r
\n" ); document.write( "\n" ); document.write( "Lori
\n" ); document.write( "

Algebra.Com's Answer #155812 by Targetweek(62)\"\" \"About 
You can put this solution on YOUR website!
Yes you are doing it correctly but you messed up when you tried to solve the quadratic equation because...
\n" ); document.write( "- \"17-y%29%5E2+%2B+y%5E2+=+169\"
\n" ); document.write( "- \"highlight%28289%29+-+34y+%2B+y%5E2+%2B+y%5E2+=+169\"
\n" ); document.write( "- \"17%5E2+=+289\" , \"17%5E2+%3C%3E+189\"
\n" ); document.write( "So besides that you did it right but i'll go ahead and finish it for you
\n" ); document.write( "- \"289+-+34y+%2B+2y%5E2+=+169\"
\n" ); document.write( "- \"2y%5E2+-+34y+%2B+289+-+169+=+169-169\"
\n" ); document.write( "- \"2y%5E2+-+34y+%2B+120+=+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 with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-34x%2B120+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-34%29%5E2-4%2A2%2A120=196\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=196 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--34%2B-sqrt%28+196+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%28-34%29%2Bsqrt%28+196+%29%29%2F2%5C2+=+12\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-34%29-sqrt%28+196+%29%29%2F2%5C2+=+5\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"2x%5E2%2B-34x%2B120\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-34x%2B120+=+2%28x-12%29%2A%28x-5%29\"
\n" ); document.write( " Again, the answer is: 12, 5.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-34%2Ax%2B120+%29\"

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\n" ); document.write( "Since your solutions for x are 12 and 5, the side lengths are 12 and 5 because you get the same answer if x=12,y=5 as x=5,y=12
\n" ); document.write( "hope that helped!
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