document.write( "Question 90758This question is from textbook Beginning Al
\n" ); document.write( ": Solve by completing the square: 4x^2 + 2x - 3 = 0
\n" ); document.write( "4x^2 + 2x = 3
\n" ); document.write( "x^2 + 2/4x = 3/4
\n" ); document.write( "Square one-half of the of the x-coefficient and then add it to both sides
\n" ); document.write( "1/2 of 2/4 = 1/4^2 = 1/16
\n" ); document.write( "x^2 + 2/4x + 1/16 = 3/4 + 1/16
\n" ); document.write( "(x-1/4)^2 = 13/16
\n" ); document.write( "x - 1/4 = +/- radical 13 over radical 16
\n" ); document.write( "x - 1/4 = +/- radical 13 over 4
\n" ); document.write( "x = 1/4 +/- radical 13 over 4
\n" ); document.write( "x = 1 +/- radical 13 over 4
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Algebra.Com's Answer #66026 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
A few minor errors in your work. The procedures you used were correct.
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\n" ); document.write( "4x^2 + 2x - 3 = 0 <=== ok
\n" ); document.write( "4x^2 + 2x = 3 <=== ok
\n" ); document.write( "x^2 + 2/4x = 3/4 <=== good!
\n" ); document.write( "Square one-half of the of the x-coefficient and then add it to both sides
\n" ); document.write( "1/2 of 2/4 = 1/4^2 = 1/16 <=== ok
\n" ); document.write( "x^2 + 2/4x + 1/16 = 3/4 + 1/16 <=== ok
\n" ); document.write( "(x-1/4)^2 = 13/16 <=== minor error. In the parentheses the sign is + not - because the
\n" ); document.write( "sign of the 2/4x term is + not minus.
\n" ); document.write( "x - 1/4 = +/- radical 13 over radical 16 <=== left side should be x + 1/4
\n" ); document.write( "x - 1/4 = +/- radical 13 over 4 <=== same. left side should be x + 1/4
\n" ); document.write( "x = 1/4 +/- radical 13 over 4 <===the right side should be -1/4 +/- (radical 13)/4
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\n" ); document.write( "This is the answer. If you want to write it as you did below you should use parentheses
\n" ); document.write( "to indicate that both terms are divided by 4.
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\n" ); document.write( "x = 1 +/- radical 13 over 4 should be x = (-1 +/- radical 13)/4
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\n" ); document.write( "This will indicate that your answer is:
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\n" ); document.write( "\"x+=+%28-1+%2B-sqrt%2813%29%29%2F4\"
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\n" ); document.write( "The way you originally wrote it implies that only the radical 13 is divided by 4 and that
\n" ); document.write( "the 1 is not. It becomes much clearer what you meant if you put the entire quantity
\n" ); document.write( "that is to be divided by 4 inside a set of parentheses.
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\n" ); document.write( "The most critical thing about your method is that you show an understanding of what you
\n" ); document.write( "are doing. A lot of students forget to divide to make the multiplier of the squared term
\n" ); document.write( "become 1. Moving the constant to the right side early in the problem is not necessary
\n" ); document.write( "but I like that you did it early in the problem. I always thought that it eliminated
\n" ); document.write( "a lot of chances for error. And you correctly divided the multiplier of the x term by 2
\n" ); document.write( "and squared it to find how much to add to each side of the equation. Good job! The only
\n" ); document.write( "check you need to make is when you write the squared term (in this problem it you wrote
\n" ); document.write( "(x -1/4)^2, the constant term (1/4) should be the same as you get when you divide the
\n" ); document.write( "multiplier of x (+2/4) by 2. In other words, when you divided the +2/4 by 2 you should have
\n" ); document.write( "gotten +1/4 and that would be the term that appears inside the parentheses.
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\n" ); document.write( "Hope this helps. Keep up the good work you are doing!!!
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