document.write( "Question 709676: find the whole number such that the twice its square added to itself makes 10\r
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Algebra.Com's Answer #436758 by jsmallt9(3758)\"\" \"About 
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Let x = the number
\n" ); document.write( "Then...
\n" ); document.write( "its square = \"x%5E2\"
\n" ); document.write( "twice its square = \"2%2Ax%5E2\"
\n" ); document.write( "twice its square added to itself = \"2%2Ax%5E2+%2B+x\" (or \"x+%2B+2%2Ax%5E2\")

\n" ); document.write( "So \"twice its square added to itself makes 10\" translates into:
\n" ); document.write( "\"2%2Ax%5E2+%2B+x+=+10\"
\n" ); document.write( "Now we solve this equation for x.

\n" ); document.write( "This is a quadratic equation so we want one side to be zero. Subtracting 10 from each side:
\n" ); document.write( "\"2%2Ax%5E2+%2B+x+-+10+=0\"
\n" ); document.write( "Next we factor (or use the Quadratic Formula). This factors without too much difficulty:
\n" ); document.write( "\"%282x%2B5%29%28x-2%29+=+0\"
\n" ); document.write( "From the Zero Product Property we know that this product can be zero only if one (or more) of the factors is zero. So:
\n" ); document.write( "2x+5 = 0 or x-2 = 0
\n" ); document.write( "Solving these we should get:
\n" ); document.write( "x = -5/2 or x = 2

\n" ); document.write( "Since the problem asks for \"whole number\" solution we will reject -5/2. So the solution to your problem is 2.
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