document.write( "Question 83586: Help Please.\r
\n" ); document.write( "\n" ); document.write( "determine whether each of the following trinomials is a perfect square. If it is, factor the trinomials.\r
\n" ); document.write( "\n" ); document.write( "x^2-24x+48
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Algebra.Com's Answer #60104 by bucky(2189)\"\" \"About 
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Is:
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\n" ); document.write( "\"x%5E2-24x%2B48\"
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\n" ); document.write( "a perfect square? The answer is, \"No, it is not.\"
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\n" ); document.write( "But how do you easily get that answer. The method to use is called \"Completing the Square.\"
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\n" ); document.write( "How do you use that method? First, make sure that the coefficient of the \"x%5E2\" term
\n" ); document.write( "is 1. [In this case it is, otherwise you would have to factor out from all the terms in
\n" ); document.write( "the trinomial the coefficient (multiplier) of the \"x%5E2\" term.]
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\n" ); document.write( "Next, forget about the +48 for the time being. Take half of the multiplier of the x term. That
\n" ); document.write( "multiplier is -24 and half of it is -12. Then square the -12 to get + 144.
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\n" ); document.write( "Now we can say that \"x%5E2+-+24x+%2B+144\" is the perfect square trinomial. [Its equivalent
\n" ); document.write( "form is \"%28x-12%29%5E2\".] So for the given trinomial to be a perfect square, the +48 would
\n" ); document.write( "have to be changed to +144.
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\n" ); document.write( "Another way to do this (maybe even easier) is to use the discriminant of the quadratic
\n" ); document.write( "formula. The quadratic formula applies to all equations of the general form:
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\n" ); document.write( "\"ax%5E2+%2B+bx+%2B+c+=+0\"
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\n" ); document.write( "The discriminant of this equation is given by \"b%5E2+-+4%2Aa%2Ac\". If the discriminant
\n" ); document.write( "is equal to zero, the trinomial is a perfect square (the equation has two real and
\n" ); document.write( "equal roots).
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\n" ); document.write( "By comparing your problem with the general form of the quadratic equation you can see
\n" ); document.write( "that a = 1, b = -24, and c = +48. Substituting these values into the discriminant,
\n" ); document.write( "you get:
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\n" ); document.write( "\"%28-24%29%5E2-+4%2A1%2A48\"
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\n" ); document.write( "This simplifies to:
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\n" ); document.write( "\"576+-+4%2A48+=+576+-192+=+384\"
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\n" ); document.write( "Since the discriminant does not equal zero, the given trinomial is not a perfect square.
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\n" ); document.write( "However, suppose that the given trinomial had been \"x%5E2+-+24x+%2B+144\". In this case
\n" ); document.write( "a = 1, b = -24, and c = 144.
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\n" ); document.write( "Substitute these values into the discriminant and you get:
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\n" ); document.write( "\"b%5E2+-+4%2Aa%2Ac+=+%28-24%29%5E2+-+4%2A1%2A144+=+576+-+576+=+0\"
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\n" ); document.write( "And since the discriminant now equals zero, this trinomial is a perfect square. [As we
\n" ); document.write( "noted earlier the trinomial \"x%5E2+-24x%2B144\" is equivalent to \"%28x-12%29%5E2\".]
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\n" ); document.write( "Hope these couple of ways help you to understand your problem better.
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