Q. A parabola opening up or down has vertex (0,4) and passes through (4,2). Write its equation in vertex form.Simplify any fractions.______
Vertex Form Explanation: What is the vertex form of the parabola?The 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)?Since the vertex is (0,4), we substitute h=0 and k=4 into the vertex form equation.y=a(x−0)2+4y=ax2+4
Use Point to Find 'a': Use the point (4,2) to find the value of 'a'.We know the parabola passes through the point (4,2), so we substitute x=4 and y=2 into the equation to solve for 'a'.2=a(4)2+42=16a+4
Solve for 'a': Solve for 'a'.Subtract 4 from both sides of the equation to isolate the term with 'a'.2−4=16a−2=16aDivide both sides by 16 to solve for 'a'.−162=a−81=a
Final Equation in Vertex Form: Write the final equation of the parabola in vertex form.Now that we have the value of a, we can write the equation of the parabola.y=(−81)x2+4This is the equation of the parabola in vertex form.
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