document.write( "Question 167340: I am having trouble understanding and solving quadratic equations. x^2-2x-13=0
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document.write( "and 4x^2-4x+3=0
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document.write( "The steps I need to use are:
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document.write( "a. move the constant term to the right side of the equation
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document.write( "b. multiply each term in the equation by four times the coefficient of the x^2 term.
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document.write( "c. square the coefficient of the original x term and add it to both sides of the equation
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document.write( "d. Take the square root from both sides
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document.write( "e. Set the left side of the equation equal to the positive square root of the number on the right side and solve for x.
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document.write( "f. set the left side of the equation equal to the negative square root of the numberon the right side of the equation and solve for x\r
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document.write( "I have to solve these kind of questions on a test and I am lost. This is what I have so far: x^2-2x-13=0
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document.write( " x^2 -2x=13
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document.write( " 4x^2-8x=52
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document.write( "Can you help me?
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document.write( "~Jenn
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document.write( "
Algebra.Com's Answer #123238 by nerdybill(7384)![]() ![]() You can put this solution on YOUR website! Your method is called \"completing the square\"... \n" ); document.write( "This site explains it quite nicely: \n" ); document.write( "http://www.purplemath.com/modules/sqrquad.htm \n" ); document.write( ". \n" ); document.write( "x^2-2x-13=0 \n" ); document.write( "x^2-2x = 13 \n" ); document.write( "Take half the 'b' coefficient and square it:[(1/2)(-2)]^2 = [-1]^1 = 1 \n" ); document.write( "x^2-2x+1 = 13+1 (since you added 1 to left, do so on the right - for balance) \n" ); document.write( "(x-1)^2 = 14 \n" ); document.write( "x-1 = sqrt(14) \n" ); document.write( "x = 1(+-)sqrt(14) \n" ); document.write( ". \n" ); document.write( "That's 1 \"plus or minus\" square root of 14. \n" ); document.write( ". \n" ); document.write( "**************************** \n" ); document.write( "4x^2-4x+3=0 \n" ); document.write( "4x^2-4x = -3 \n" ); document.write( "factor the 4 on the left: \n" ); document.write( "4(x^2-x) = -3 \n" ); document.write( "(x^2-x) = -3/4 \n" ); document.write( "(x^2-x+(1/4)) = -3/4 + 1/4 \n" ); document.write( "(x-(1/2))^2 = -2/4 \n" ); document.write( "x-(1/2) = sqrt(-2/4) \n" ); document.write( "x = (1/2)(+-)sqrt(-1/2) \n" ); document.write( ". \n" ); document.write( "Since the term inside the sqrt is negative -- we have no real solutions -- rather, we have two imaginary solutions. \n" ); document.write( ". \n" ); document.write( "You could see the same thing using the \"quadratic equation\" below: \n" ); document.write( "
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