Q. A parabola opening up or down has vertex (0,1) and passes through (12,−11). Write its equation in vertex form.Simplify any fractions.
Vertex Form Explanation: 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 (0,1)?Substitute 0 for h and 1 for k in the vertex form.y=a(x−0)2+1y=ax2+1
Use Point to Find a: Use the point (12,−11) to find the value of a. Replace the variables with (12,−11) in the equation. Substitute 12 for x and −11 for y. −11=a(12)2+1−11=144a+1
Solve for a: Solve for a.−11=144a+1Subtract 1 from both sides.−12=144aDivide both sides by 144.a=−14412a=−121
Write Equation with a: Write the equation of the parabola in vertex form using the value of a. Substitute −121 for a in the equation y=ax2+1. y=(−121)x2+1 Vertex form of the parabola: y=−121x2+1
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