Q. What is the range of this quadratic function?y=x2+12x+20Choices:(A){y∣y≤−6}(B){y∣y≥−6}(C){y∣y≥−16}(D)all real numbers
Calculate x-coordinate of vertex: We have the quadratic function y=x2+12x+20. To find the range, we need to determine the vertex of the parabola. The x-coordinate of the vertex is given by the formula x=−2ab. In our equation, a=1 and b=12.Calculate the x-coordinate of the vertex:x=−2×112x=−212x=−6
Calculate y-coordinate of vertex: Now that we have the x-coordinate of the vertex, we need to find the corresponding y-coordinate by substituting x=−6 into the original equation.Calculate the y-coordinate when x=−6:y=(−6)2+12∗(−6)+20y=36−72+20y=−36+20y=−16
Determine vertex of parabola: The vertex of the parabola is at the point (−6,−16). Since the coefficient of x2 is positive (a=1), the parabola opens upwards. This means that the vertex represents the minimum point of the parabola.
Find range of function: Since the parabola opens upwards and the vertex is the lowest point, the range of the function is all y-values greater than or equal to the y-coordinate of the vertex.The range of the function is {y∣y≥−16}.
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