How do I solve a quadratic equation by competing the square?

How would you solve  x2+8x+16=81Show that this can be factorised (x+4)2=92Which can then be easily solved by square rooting both sides
What if we could now use this method to solve all quadratics?!!?
Consider Solve  x2+6x+1=0
We can complete the square by:(x+3)2-9+1=0 (x+3)2-8=0 (x+3)2=8 (x+3)=±√8 x=-3±2√2

Related Maths GCSE answers

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Ben wants to book tickets to see a concert. The price of the ticket is £65. He must also pay a booking fee, which is 15% of the ticket price. Ben has £75, does he have enough money to pay for the ticket and booking fee?


simplify fully: (3x^2 - 8x -3)/(2x^2 -6x)


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Prove that the composite function fg(2)=-26 where f(x)=3x+1 and g(x)=1-5x


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