Q. A parabola opening up or down has vertex (0,2) and passes through (4,−2). Write its equation in vertex form.Simplify any fractions.
Identify vertex form: Identify the vertex form of a 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.
Plug vertex coordinates: Plug the vertex coordinates into the vertex form.Since the vertex is given as (0,2), we substitute h=0 and k=2 into the vertex form equation.y=a(x−0)2+2y=ax2+2
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 can substitute x=4 and y=−2 into the equation to solve for 'a'.−2=a(4)2+2−2=16a+2
Solve for 'a': Solve for 'a'.Subtract 2 from both sides of the equation to isolate the term with 'a'.−2−2=16a−4=16aDivide both sides by 16 to solve for 'a'.a=−4/16a=−1/4
Write final equation: 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=(−41)x2+2This is the equation of the parabola in vertex form.
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