Question
find the axis of symmetry of the following quadratic function by completing the square
f(x)=x^2+8x
a. x=4
b.x=-16
c. x=16
d. x=-4
f(x)=x^2+8x
a. x=4
b.x=-16
c. x=16
d. x=-4
Answers
GPT 3.5
To find the axis of symmetry of the quadratic function f(x) = x^2 + 8x, we need to complete the square.
f(x) = x^2 + 8x
f(x) = (x^2 + 8x + 16) - 16
f(x) = (x + 4)^2 - 16
The axis of symmetry of a quadratic function in the form f(x) = (x - h)^2 + k is x = h. Therefore, the axis of symmetry of the function f(x) = x^2 + 8x is x = -4.
So, the correct answer is: d. x = -4
f(x) = x^2 + 8x
f(x) = (x^2 + 8x + 16) - 16
f(x) = (x + 4)^2 - 16
The axis of symmetry of a quadratic function in the form f(x) = (x - h)^2 + k is x = h. Therefore, the axis of symmetry of the function f(x) = x^2 + 8x is x = -4.
So, the correct answer is: d. x = -4