Q. Rewrite the function by completing the square.f(x)=x2−16x−100f(x)=(x+□)2+□
Given quadratic function: We start with the given quadratic function:f(x) = x2−16x−100Our goal is to rewrite this function in the form of (x+a)2+b.
Completing the square: To complete the square, we need to find a value that, when added and subtracted to the x2−16x part, completes the square. This value is found by taking half of the coefficient of x, squaring it, and then adding it to both sides.The coefficient of x is −16, so half of −16 is −8, and (−8)2=64.
Adding and subtracting: We add and subtract 64 to the function to complete the square:f(x)=x2−16x+64−64−100Now we have a perfect square trinomial x2−16x+64 and a constant −164.
Factoring the perfect square trinomial: We factor the perfect square trinomial:f(x) = (x - 8)^2 - 164Now the function is in the completed square form.
Checking the work: We check our work by expanding (x−8)2 to ensure it gives us back the original x2−16x term:(x−8)2=x2−16x+64This matches the x2−16x+64 part of our function, so there is no math error.
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