Q. A parabola has a vertex at (−4,−2) and goes through the point (−8,30). Determine its equation in vertex form and rewrite equation in standard form.
Identify vertex values: Identify the vertex values h and k from the given vertex (−4,−2).h=−4, k=−2
Write vertex form equation: Write the vertex form equation using the values of h and k.Vertex form: y=a(x−h)2+kSubstitute h=−4 and k=−2:y=a(x+4)2−2
Find value of a: Use the point (−8,30) to find the value of a. Substitute x=−8 and y=30 into the equation: 30=a(−8+4)2−230=a(−4)2−230=16a−232=16aa=1632a=2
Substitute value of a: Substitute the value of a back into the vertex form equation.y=2(x+4)2−2
Expand to standard form: Expand the vertex form to standard form.y=2(x2+8x+16)−2y=2x2+16x+32−2y=2x2+16x+30
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