Q. A parabola opening up or down has vertex (0,1) and passes through (8,−15). Write its equation in vertex form.Simplify any fractions.
Vertex Form: 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.
Vertex at (0,1): What is the equation of a parabola with a vertex at (0,1)?Substitute 0 for h and 1 for k in the vertex form.y=a(x−0)2+1y=ax2+1
Find Value of a: Use the point (8,−15) to find the value of a. Replace the variables with (8,−15) in the equation. Substitute 8 for x and −15 for y. −15=a(8)2+1−15=64a+1
Solve for a: Solve for a.−15=64a+1Subtract 1 from both sides.−16=64aDivide both sides by 64.−6416=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=(−41)x2+1Vertex form of the parabola: y=−41x2+1
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