Function f is a quadratic function. The graph of y=f(x) in the xy-plane has a vertex at (6,10), contains the point (5,8), and has a y-intercept at (0,a). The graph of y=4f(x) has a y-intercept at (0,b). What is the positive difference between a and b?
Q. Function f is a quadratic function. The graph of y=f(x) in the xy-plane has a vertex at (6,10), contains the point (5,8), and has a y-intercept at (0,a). The graph of y=4f(x) has a y-intercept at (0,b). What is the positive difference between a and b?
Vertex Form Equation: Vertex form of quadratic function: y=a(x−h)2+kGiven vertex: (6, 10)Equation: y=a(x−6)2+10
Substitute Point: Point (5, 8) lies on the parabola.Substitute (5, 8) into the equation: 8=a(5−6)2+108=a(1)2+108=a+10Solve for a: a=−2
Find Y-Intercept: Equation of the parabola: y=−2(x−6)2+10Find y-intercept (0, a): Substitute x = 0: y=−2(0−6)2+10y=−2(36)+10y=−72+10y=−62So, a = −62
Graph Transformation: Graph of y=4f(x)New equation: y=4[−2(x−6)2+10]y=−8(x−6)2+40Find y-intercept (0, b):Substitute x = 0: y=−8(0−6)2+40y=−8(36)+40y=−288+40y=−248So, b = −248
Calculate Positive Difference: Positive difference between a and b:∣a−b∣=∣−62−(−248)∣∣a−b∣=∣−62+248∣∣a−b∣=∣186∣Positive difference = 186
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