Complete the square of the equation below.

Q. Complete the square : x2 + 4x - 12A. Completing the square is putting the given equation into the form (x + a) 2 + bFirst, a = the coefficient of x 2so in this case a = 4 = 2 Then to find b we calculate how to get to our desired equation from the expansion of (x + a)2so in our example we calculate (x + 2)2= (x + 2) (x + 2) = x2 + 4x + 4but we want x2 + 4x - 12so how do we get from 4 to -12?-12- 4 = -16 = bNow we have found both answers, don’t forget to sub them back into the desired format to get us that last mark!!!ANS = (x + 2)2 -16

Answered by Victoria Y. Maths tutor

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