Q. A parabola opening up or down has vertex (0,4) and passes through (8,−4). 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
Use Point for 'a': Use the point (8,−4) to find the value of 'a'.Replace the variables with (8,−4) in the equation.Substitute 8 for x and −4 for y.−4=a(8)2+4−4=64a+4
Solve for 'a': Solve for 'a'.−4=64a+4Subtract 4 from both sides to isolate the term with 'a'.−4−4=64a+4−4−8=64aDivide both sides by 64 to solve for 'a'.−648=a−81=a
Write Final Equation: Write the equation of the parabola with the found value of 'a'.Substitute −81 for a in the equation y=ax2+4.y=(−81)x2+4Vertex form of the parabola: y=−(81)x2+4
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