Q. A parabola opening up or down has vertex (0,−7) and passes through (8,1). Write its equation in vertex form.Simplify any fractions.
Identify Vertex Values: We have:Vertex: (0,−7)Identify the values of h and k.Vertex is (0,−7).h=0k=−7
Select Equation: We have:y=a(x−h)2+kh=0 and k=−7Select the equation after substituting the values of h and k.Substitute h=0 and k=−7 in y=a(x−h)2+k.y=a(x−0)2−7y=ax2−7
Find Value of a: We have: y=ax2−7 Point: (8,1) Find the value of a. y=ax2−7 1=a(8)2−7 1=64a−7 1+7=64a 8=64a 648=a a=81
Write Vertex Form: We found:a=81h=0k=−7Write the equation of a parabola in vertex form.y=a(x−h)2+ky=81(x−0)2−7Vertex form: y=81x2−7
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