Q. A parabola opening up or down has vertex (0,4) and passes through (8,−12). Write its equation in vertex form.Simplify any fractions.
Vertex Form Explanation: What is the vertex form of the parabola?Vertex form of a parabola is given by the equation y=a(x−h)2+k, where (h,k) is the vertex of the parabola.
Equation with Vertex: What is the equation of a parabola with a vertex at (0,4)?Substitute 0 for h and 4 for k in the vertex form.y=a(x−0)2+4y=ax2+4
Finding Value of 'a': Use the point (8,−12) to find the value of 'a'.Replace the variables with (8,−12) in the equation.Substitute 8 for x and −12 for y.−12=a(8)2+4−12=64a+4
Solving for 'a': Solve for 'a'.−12=64a+4Subtract 4 from both sides.−12−4=64a−16=64aDivide both sides by 64.−6416=a−41=a
Final Parabola Equation: Write the equation of the parabola using the value of a.Substitute −41 for a in the equation y=ax2+4.y=(−41)x2+4Vertex form of the parabola: y=−(41)x2+4
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