Q. A parabola opening up or down has vertex (0,−5) and passes through (4,−4). 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,−5), we substitute h=0 and k=−5 into the vertex form equation.y=a(x−0)2−5y=ax2−5
Use point to find 'a': Use the point (4,−4) to find the value of 'a'.We know that the parabola passes through the point (4,−4), so we substitute x=4 and y=−4 into the equation to solve for 'a'.−4=a(4)2−5−4=16a−5
Solve for 'a': Solve for 'a'.Add 5 to both sides of the equation to isolate the term with 'a'.−4+5=16a−5+51=16aDivide both sides by 16 to solve for 'a'.161=a
Write final equation: Write the final equation of the parabola in vertex form.Now that we have the value of ' extit{a}', we can write the equation of the parabola.y=161x2−5
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