document.write( "Question 904410: Do I have this quadratic to standard form problem correct?
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Algebra.Com's Answer #548673 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
unfortunately no.\r
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\n" ); document.write( "\n" ); document.write( "let me show you how to do it and you should be able to see where you went wrong.\r
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\n" ); document.write( "\n" ); document.write( "start with g(x) = \"5x%5E2+-+30x+%2B+55\"\r
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\n" ); document.write( "\n" ); document.write( "factor out the 5 to get g(x) = \"5%2A%28x%5E2+-+6x+%2B+11%29\"\r
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\n" ); document.write( "\n" ); document.write( "complete the square within the parentheses to get g(x) = \"5%2A%28%28x-3%29%5E2-9%2B11%29\"\r
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\n" ); document.write( "\n" ); document.write( "simplify by applying the distributive law of multiplication to get g(x) = \"5%2A%28x-3%29%5E2+-+5%2A9+%2B+5%2A11\" which can be simplified to \"5%2A%28x-3%29%5E2+-+45+%2B+55\".\r
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\n" ); document.write( "\n" ); document.write( "simplify further by combining like terms to get g(x) = \"5%2A%28x-3%29%5E2+%2B+10\"\r
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\n" ); document.write( "\n" ); document.write( "to determine if the standard form is equivalent to your original form, then simply pick a value of x at random and solve each of the equations for that value of x.\r
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\n" ); document.write( "\n" ); document.write( "for example:\r
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\n" ); document.write( "\n" ); document.write( "when x = 20, the original equation becomes g(20) = \"5%2A20%5E2+-30%2A20\" + 55 which becomes g(20) = 1455.\r
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\n" ); document.write( "\n" ); document.write( "when x = 20, the standard form equation becomes (g(20) = \"5%2A15%2820-3%29%5E2%2B10\" which becomes g(20) = 1455.\r
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\n" ); document.write( "\n" ); document.write( "both forms give you the same answer which is a good indication that you translates correctly.\r
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\n" ); document.write( "\n" ); document.write( "factoring by completing the square is tricky until you get the hang of it.\r
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\n" ); document.write( "\n" ); document.write( "you have to do a few before you become comfortable with it.\r
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\n" ); document.write( "\n" ); document.write( "some instructions will have you separate out the constant term.\r
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\n" ); document.write( "\n" ); document.write( "it winds up being the same thing with perhaps one less computation.\r
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\n" ); document.write( "\n" ); document.write( "let me do it that way so you can see how it's done.\r
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\n" ); document.write( "\n" ); document.write( "start with g(x) = \"5x%5E2+-+30x+%2B+55\" as before.\r
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\n" ); document.write( "\n" ); document.write( "separate the x terms and the constant terms so they will be shown separately as follows:\r
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\n" ); document.write( "\n" ); document.write( "g(x) = \"%285x%5E2+-+30x%29+%2B+55\"\r
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\n" ); document.write( "\n" ); document.write( "the 5x^2 - 30x has been enclosed in a set of parentheses to group those terms together.\r
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\n" ); document.write( "\n" ); document.write( "now factor out the 5 from the x terms to get g(x) = \"5%2A%28x%5E2+-+6x%29+%2B+55\"\r
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\n" ); document.write( "\n" ); document.write( "now take half of the coefficient of the x term and complete the squares to get g(x) = \"5%2A%28x-3%29%5E2+-+9%29+%2B+55\"\r
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\n" ); document.write( "\n" ); document.write( "why did you have to subtract the 9?\r
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\n" ); document.write( "\n" ); document.write( "before we go through that, the 9 is the result of half the coefficient of the x term squared.\r
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\n" ); document.write( "\n" ); document.write( "when you take x^2 - 6x and take half the coefficient of the x term and replace it with \"%28x-3%29%5E2\", you get \"%28x-3%29%5E2+=+x%5E2+-+6x+%2B+9\".\r
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\n" ); document.write( "\n" ); document.write( "this means you have 9 more than you wanted.\r
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\n" ); document.write( "\n" ); document.write( "the 9 happens to be half of the coefficient of the x term squared.\r
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\n" ); document.write( "\n" ); document.write( "so you subtract 9 and you get \"%28x-3%29%5E2+-+9\" = \"x%5E2+-+6x+%2B+9+-+9\" which results in \"x%5E2+-+6x\" which is what you want.\r
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\n" ); document.write( "\n" ); document.write( "so \"%28x%5E2+-+6x%29\" is equal to \"%28%28x-3%29%5E2+-+9%29\".\r
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\n" ); document.write( "\n" ); document.write( "all of that stays within the parentheses.\r
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\n" ); document.write( "\n" ); document.write( "you started with g(x) = \"5%2A%28x%5E2+-+6x%29+%2B+55\" and you ended up with g(x) = \"5%2A%28%28x-3%29%5E2+-+9%29+%2B+55\".\r
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\n" ); document.write( "\n" ); document.write( "now you want to remove the parentheses by applying the distributive law of multiplication to get g(x) = \"5%2A%28x-3%29%5E2+-+45+%2B+55\".\r
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\n" ); document.write( "\n" ); document.write( "now you want to simplify further by combining like terms to get g(x) = \"5%2A%28x-3%29%5E2+%2B+10\".\r
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\n" ); document.write( "\n" ); document.write( "same answer as before except you didn't factor out the 5 from the constant term.\r
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