document.write( "Question 622630: Solve the equation by factorisation method x^2+(x+2)^2=650\r
\n" ); document.write( "\n" ); document.write( "I attempted the question but I am stuck at this step
\n" ); document.write( "x^2+x^2+4-650=0
\n" ); document.write( "2x^2-646=0
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Algebra.Com's Answer #391482 by math-vortex(648)\"\" \"About 
You can put this solution on YOUR website!
Hi there,
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\n" ); document.write( "Solve the equation by factorization method.
\n" ); document.write( "\"+x%5E2%2B%28x%2B2%29%5E2=650\"
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\n" ); document.write( "I see one problem: \"%28x%2B2%29%5E2%3C%3Ex%5E2%2B4\". You need to expand it out like this:
\n" ); document.write( "\"%28x%2B2%29%5E2=%28x%2B2%29%28x%2B2%29\"
\n" ); document.write( "\"%28x%2B2%29%5E2=x%5E2%2B2x%2B2x%2B4\"
\n" ); document.write( "\"%28x%2B2%29%5E2=x%5E2%2B4x%2B4\"
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\n" ); document.write( "You can probably take it from there, but I'll continue on just in case.
\n" ); document.write( "\"x%5E2%2B%28x%2B2%29%5E2=650\"
\n" ); document.write( "\"x%5E2%2B%28x%5E2%2B4x%2B4%29=650\"
\n" ); document.write( "\"2x%5E2%2B4x-646=0\"
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\n" ); document.write( "I find it much easier to factor when the leading coefficient is 1, so I will divide both sides of the equation by 2. (This step is not necessary, but it won't change the answer either.)
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\n" ); document.write( "\"x%5E2%2B2x-323=0\"
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\n" ); document.write( "In order to factor this equation, we want two numbers whose product is -323 and whose sum is 2. It turns out that 17*19=323. I figured this out by checking the prime numbers (2, 3, 5, 7, 11, ...) until I found one that worked. The numbers we want are -17 and 19; their product is -323 and their sum is 2.
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\n" ); document.write( "\"x%5E2%2B2x-323=%28x-17%29%28x%2B19%29=0\"
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\n" ); document.write( "Since the product of these factors is 0, either \"x-17=0\" or \"x%2B19=0\".
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\n" ); document.write( "Therefore, x=17 or x=-19.
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\n" ); document.write( "It's always a good idea to check the answers in the original problem.
\n" ); document.write( "x=17:
\n" ); document.write( "\"+x%5E2%2B%28x%2B2%29%5E2=650\"
\n" ); document.write( "\"+%2817%29%5E2%2B%2817%2B2%29%5E2=650\"
\n" ); document.write( "\"289%2B361=650\"
\n" ); document.write( "\"650=650\" Check!!!
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\n" ); document.write( "x=-19
\n" ); document.write( "\"+x%5E2%2B%28x%2B2%29%5E2=650\"
\n" ); document.write( "\"+%28-19%29%5E2%2B%28-19%2B2%29%5E2=650\"
\n" ); document.write( "\"361%2B289=650\"
\n" ); document.write( "\"650=650\" Check! Check!
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\n" ); document.write( "Hope this helps! Feel free to email if you still have questions about this.
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\n" ); document.write( "Ms.Figgy
\n" ); document.write( "math.in.the.vortex@gmail.com
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