How do you complete the square? example: x^2 + 8x + 13=0
the method to complete the square is as follows; -take the constant (13) away from both sides of the equation leaving x and x^2 terms only on one side of the equation: x^2+8x=-13
-Add half of the value of the coefficient of x, squared,to both sides of the equation((8/2)^2) : x^2+8x+16=-13+16 x^2+8x+16=3,
-factorise the left hand side of the equation to give: (x+4)^2=3, (completed the square) -to then find x; x+4=+root(3) or -root(3) x=root(3)-4 or x=-4-root(3) you can test your answer but putting it back into the original equation.
JM
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