document.write( "Question 761792: two squares have sides x cm and(x+4)cm .the sum of their areas is 656 sq.cm. express this as an algebraic equation in x and solve the equation to find the sides of the squares \n" ); document.write( "
Algebra.Com's Answer #463473 by ramkikk66(644)\"\" \"About 
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Area of 1st square = \"x%5E2\"\r
\n" ); document.write( "\n" ); document.write( "Area of 2nd square = \"%28x%2B4%29%5E2+=+x%5E2+%2B+8%2Ax+%2B+16\"\r
\n" ); document.write( "\n" ); document.write( "Sum of areas = \"x%5E2+%2B+x%5E2+%2B+8%2Ax+%2B+16+=+656\"\r
\n" ); document.write( "\n" ); document.write( "Simplifying and subtracting 656 from both sides\r
\n" ); document.write( "\n" ); document.write( "\"2%2Ax%5E2+%2B+8%2Ax+-+640+=+0\"\r
\n" ); document.write( "\n" ); document.write( "Dividing by 2\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+%2B+4%2Ax+-+320+=+0\"\r
\n" ); document.write( "\n" ); document.write( "This is a standard quadratic equation of the form ax^2 + bx + c = 0 with a = 1, b = 4 and c = -320.\r
\n" ); document.write( "\n" ); document.write( "Solving it using the quadratic solver (see below), we get the values of x as\r
\n" ); document.write( "\n" ); document.write( "\"x+=+16\" or \"x+=+-20\"\r
\n" ); document.write( "\n" ); document.write( "Since x cannot be negative, x = 16\r
\n" ); document.write( "\n" ); document.write( "So, side of 1st square = \"highlight%2816%29\" and side of second square = \"highlight%2820%29\"\r
\n" ); document.write( "\n" ); document.write( "Sum of areas = \"256+%2B+400+=+656\". Check!\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B4x%2B-320+=+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=%284%29%5E2-4%2A1%2A-320=1296\".
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\n" ); document.write( " Discriminant d=1296 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-4%2B-sqrt%28+1296+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%284%29%2Bsqrt%28+1296+%29%29%2F2%5C1+=+16\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%284%29-sqrt%28+1296+%29%29%2F2%5C1+=+-20\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B4x%2B-320\" can be factored:
\n" ); document.write( " \"1x%5E2%2B4x%2B-320+=+1%28x-16%29%2A%28x--20%29\"
\n" ); document.write( " Again, the answer is: 16, -20.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B4%2Ax%2B-320+%29\"
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