Q. Rewrite the equation by completing the square.x2+18x+80=0(x+□)2=□
Given equation: Start with the given equation x2+18x+80=0.To complete the square, we need to form a perfect square trinomial on the left side of the equation.
Completing the square: To create a perfect square trinomial, we need to find a value that, when added and subtracted to the equation, completes the square for x2+18x. This value is (218)2=92=81.
Adding and subtracting 81: Add and subtract 81 inside the equation to complete the square. We add 81 to create the perfect square trinomial and subtract 81 to keep the equation balanced.x2+18x+81−81+80=0
Combining like terms: Combine like terms on the left side of the equation. x2+18x+81=81−80x2+18x+81=1
Rewriting as a perfect square trinomial: Now, the left side of the equation is a perfect square trinomial, and we can rewrite it as the square of a binomial. (x+9)2=1
Completing the square: The equation is now rewritten by completing the square. x2+18x+80=0, (x+9)2=1
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