Q. A parabola opening up or down has vertex (0,−2) and passes through (−4,−4). Write its equation in vertex form.Simplify any fractions.
Identify Vertex Form: Identify the vertex form of a 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.
Substitute Vertex: Substitute the vertex into the vertex form.Given the vertex (0,−2), we substitute h=0 and k=−2 into the vertex form equation.y=a(x−0)2−2y=ax2−2
Use Point to Find 'a': Use the point (−4,−4) to find the value of 'a'.The parabola passes through the point (−4,−4), so we substitute x=−4 and y=−4 into the equation to solve for 'a'.−4=a(−4)2−2−4=16a−2
Solve for 'a': Solve for 'a'.Add 2 to both sides of the equation to isolate the term with 'a'.−4+2=16a−2=16aDivide both sides by 16 to solve for 'a'.−2/16=a−1/8=a
Write Final Equation: Write the final equation of the parabola in vertex form.Now that we have found a to be −81, we substitute it back into the vertex form equation.y=(−81)(x−0)2−2y=−(81)x2−2This is the equation of the parabola in vertex form.
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