document.write( "Question 167340: I am having trouble understanding and solving quadratic equations. x^2-2x-13=0
\n" ); document.write( "and 4x^2-4x+3=0
\n" ); document.write( "The steps I need to use are:
\n" ); document.write( "a. move the constant term to the right side of the equation
\n" ); document.write( "b. multiply each term in the equation by four times the coefficient of the x^2 term.
\n" ); document.write( "c. square the coefficient of the original x term and add it to both sides of the equation
\n" ); document.write( "d. Take the square root from both sides
\n" ); 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.
\n" ); 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
\n" ); document.write( "\n" ); 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
\n" ); document.write( " x^2 -2x=13
\n" ); document.write( " 4x^2-8x=52
\n" ); document.write( "Can you help me?
\n" ); document.write( "~Jenn
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Algebra.Com's Answer #123238 by nerdybill(7384)\"\" \"About 
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)
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\n" ); document.write( "That's 1 \"plus or minus\" square root of 14.
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\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.
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\n" ); document.write( "You could see the same thing using the \"quadratic equation\" below:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"4x%5E2%2B-4x%2B3+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-4%29%5E2-4%2A4%2A3=-32\".
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\n" ); document.write( " The discriminant -32 is less than zero. That means that there are no solutions among real numbers.

\n" ); document.write( " If you are a student of advanced school algebra and are aware about imaginary numbers, read on.

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\n" ); document.write( " In the field of imaginary numbers, the square root of -32 is + or - \"sqrt%28+32%29+=+5.65685424949238\".
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\n" ); document.write( " The solution is
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\n" ); document.write( " Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-4%2Ax%2B3+%29\"

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