Q. A parabola opening up or down has vertex (0,−6) and passes through (10,19). Write its equation in vertex form.Simplify any fractions.
Identify h and k: We have:Vertex: (0,−6)Identify the values of h and k.Vertex is (0,−6).h=0k=−6
Select equation with h and k: We have:y=a(x−h)2+kh=0 and k=−6Select the equation after substituting the values of h and k.Substitute h=0 and k=−6 in y=a(x−h)2+k.y=a(x−0)2−6y=ax2−6
Find value of a: We have: y=ax2−6Point: (10,19)Find the value of a.y=ax2−619=a(10)2−619=100a−619+6=100a25=100a10025=ay=ax2−60
Write parabola equation: We found:a=41h=0k=−6Write the equation of a parabola in vertex form.y=a(x−h)2+ky=41(x−0)2−6Vertex form: y=41x2−6
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