Q. A parabola opening up or down has vertex (0,−3) and passes through (8,−19). 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,−3), we substitute h=0 and k=−3 into the vertex form equation.y=a(x−0)2−3y=ax2−3
Use point to find 'a': Use the point (8,−19) to find the value of 'a'.We know the parabola passes through the point (8,−19), so we can substitute x=8 and y=−19 into the equation to solve for 'a'.−19=a(8)2−3−19=64a−3
Solve for 'a': Solve for 'a'.Now we isolate 'a' by adding 3 to both sides and then dividing by 64.−19+3=64a−16=64aa=−16/64a=−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)(x−0)2−3Simplifying further, we get:y=−41x2−3
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