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.
Identify Vertex Values: We have:Vertex: (0,−1)Identify the values of h and k.Vertex is (0,−1).h=0k=−1
Select Equation with Substitution: We have:y=a(x−h)2+kh=0 and k=−1Select the equation after substituting the values of h and k.Substitute h=0 and k=−1 in y=a(x−h)2+k.y=a(x−0)2−1y=ax2−1
Find Value of a: We have: y=ax2−1 Point: (12,11) Find the value of a. y=ax2−1 11=a(12)2−1 11+1=a×144 12=a×144 14412=144(a×144) a=121
Write Parabola Equation in Vertex Form: We found:a=121h=0k=−1Write the equation of a parabola in vertex form.y=a(x−h)2+ky=121(x−0)2−1Vertex form: y=121x2−1
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