Q. A parabola opening up or down has vertex (0,−2) and passes through (8,−10). Write its equation in vertex form.Simplify any fractions.
Vertex Form Explanation: What is the vertex form of the parabola?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,−2)?Substitute 0 for h and −2 for k in the vertex form.y=a(x−0)2+(−2)y=ax2−2
Use Point for Value: Use the point (8,−10) to find the value of a. Replace the variables with (8,−10) in the equation. Substitute 8 for x and −10 for y. −10=a(8)2−2−10=64a−2
Solve for a: Solve for a.−10=64a−2Add 2 to both sides of the equation.−8=64aDivide both sides by 64.−648=aSimplify the fraction.−81=a
Equation with a=−81: What is the equation of the parabola if a=−81?Substitute −81 for a in the equation y=ax2−2.y=(−81)x2−2Vertex form of the parabola: y=−81x2−2
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