Q. What is the range of this quadratic function?y=x2−12x+27Choices:(A)y∣y≥9(B)y∣y≥6(C)y∣y≥−9(D)all real numbers
Identify quadratic function: Identify the quadratic function.We have the quadratic function y=x2−12x+27. We need to find the range of this function.
Find vertex x-coordinate: Find the x-coordinate of the vertex.The x-coordinate of the vertex of a quadratic function in the form y=ax2+bx+c is given by x=−2ab. Here, a=1 and b=−12.x=−(−12)/(2⋅1)x=212x=6
Find vertex y-coordinate: Find the y-coordinate of the vertex.Substitute x=6 into the quadratic function to find the corresponding y-coordinate.y=(6)2−12(6)+27y=36−72+27y=−36+27y=−9
Determine parabola direction: Determine the direction of the parabola. Since a=1 and a > 0, the parabola opens upwards.
Find range of function: Find the range of the function.The vertex of the parabola is (6,−9), and since the parabola opens upwards, the y-values must be greater than or equal to the y-coordinate of the vertex.Range: \{y∣y≥−9\}
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