Q. Rewrite the function by completing the square.f(x)=x2+20x−86f(x)=(x+□)2+□
Given quadratic function: We start with the given quadratic function:f(x) = x^2 + 20x - 86To complete the square, we need to form a perfect square trinomial from the x^2 and x terms. We will find the value to add and subtract to complete the square.
Completing the square: The coefficient of x is 20. To complete the square, we take half of the coefficient of x, square it, and add it to and subtract it from the equation. This value is (220)2=102=100.
Adding and subtracting 100: We add and subtract 100 inside the function:f(x) = (x2+20x+100)−100−86Now we have a perfect square trinomial x2+20x+100, which can be factored into (x+10)2.
Factoring the perfect square trinomial: We simplify the constants −100 and −86:f(x) = (x + 10)^2 - 100 - 86f(x) = (x + 10)^2 - 186Now the function is written in the completed square form.
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