Q. A parabola opening up or down has vertex (0,−3) and passes through (−6,−12). Write its equation in vertex form.Simplify any fractions.
Vertex Form of Parabola: 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,−3)?Substitute 0 for h and −3 for k in the vertex form.y=a(x−0)2+(−3)y=ax2−3
Use Point to Find a: Use the point (−6,−12) to find the value of a.Replace the variables with (−6,−12) in the equation.Substitute −6 for x and −12 for y.−12=a(−6)2−3−12=36a−3
Solve for a: Solve for a.−12=36a−3Add 3 to both sides.−9=36aDivide both sides by 36.−369=aSimplify the fraction.−41=a
Equation with a=−41: What is the equation of the parabola if a=−41?Substitute −41 for a in the equation y=ax2−3.y=(−41)x2−3Vertex form of the parabola: y=−41x2−3
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