By completing the square, find the solutions of x which satisfy the equation x^2+14x-1=0
Using the general complete the square formula, where x2+bx+c=0 becomes (a+b/2)2+b2+c=0, we get (x+7)2-72-1=0 This can be rearranged to show that (x+7)2=50 by taking the square root of both sides we find that x+7=+ or - √50 Hence the final solutions are x=-7 +√50 and x=-7-√50
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