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You can put this solution on YOUR website!
To complete the square we have to get the equation into the proper form, which is: x^2+bx = c
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\n" ); document.write( "5x^2-9x+4 = 0
\n" ); document.write( "5x^2+(-9)x = -4
\n" ); document.write( "[5x^2+(-9)x]/5 = -4/5
\n" ); document.write( "x^2+(-9/5)x = -4/5
\n" ); document.write( "now take the coefficient of x, which is -9/5, and divide it by 2. All you have to do is multiply the divisor, 5, times 2 and you've automatically divided -9/5 by 2: -9/5 divided by 2 becomes -9/10. Square this number (when you square a negative it becomes positive because -*- = +): 81/100 Now add this number to both sides of the equation:
\n" ); document.write( "x^2+(-9/10)x+81/100 = -4/5+81/100 add on the right (find a common denominator and add the numerators):
\n" ); document.write( "x^2+(-9/10)x+81/100 = 1/100
\n" ); document.write( "factor the left side:
\n" ); document.write( "(x-9/10)^2 = 1/100
\n" ); document.write( "Take the square root of both sides and you get:
\n" ); document.write( "x-9/10 = 1/10 or x-9/10 = -1/10
\n" ); document.write( "add 9/10 on both sides of both equations
\n" ); document.write( "x = 1 or x = 8/10 = 4/5 = 0.8 if you need it in decimals.
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\n" ); document.write( "John\r
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