Q. A parabola opening up or down has vertex (0,1) and passes through (−8,9). 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 (−8,9) to find the value of 'a'.Replace the variables with (−8,9) in the equation.Substitute −8 for x and 9 for y.9=a(−8)2+19=64a+1
Solve for 'a': Solve for 'a'.9=64a+1Subtract 1 from both sides.8=64aDivide both sides by 64.648=a81=a
Write Equation with 'a': Write the equation of the parabola with the value of 'a'.Substitute 81 for a in the equation y=ax2+1.y=(81)x2+1Vertex form of the parabola: y=(81)x2+1
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