Write x^2+6x-7 in the form (x+a)^2+b where a and b are integers
Complete the square.We want a quadratic we can simplify.Halve the linear term coefficient (6) and square it.Add it to the (x2+6x) term and subtract it from the 7.x2+6x+(6/2)2-7-(6/2)2As you can see the equation still holds true as the +(6/2)2 and -(6/2)2 cancels out.Gives x2+6x+9-7-9x2+6x+9 simplifies to (x+3)(x+3) or (x+3)2Left with (x+3)2-16
GB
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