How do you complete the square?
Completing the square is often useful when solving equations! An example: x2 +6x-7=0. Step 1) We want to move the constant to the right hand side: x2+6x=7. Step 2) Now, add the square of the coefficient of x on to both sides: x2+6x+32=7+32 -> x2+6x+9=16. Step 3) Factorise the left hand side: (x+3)2=16. Step 4) Square root the equation and solve: x+3=+/-4 -> x=-3+/-4.
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