Q. A parabola opening up or down has vertex (0,−2) and passes through (4,2). Write its equation in vertex form.Simplify any fractions.
Vertex Form Explanation: What is the vertex form of the 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.
Equation with Vertex: What is the equation of a parabola with a vertex at (0,−2)?Since the vertex is (0,−2), we substitute h=0 and k=−2 into the vertex form equation.y=a(x−0)2−2y=ax2−2
Use Point (4,2): Use the point (4,2) to find the value of a. We know the parabola passes through the point (4,2), so we substitute x=4 and y=2 into the equation to solve for a. 2=a(4)2−22=16a−2
Solve for 'a': Solve for 'a'.Add 2 to both sides of the equation to isolate the term with 'a'.2+2=16a4=16aDivide both sides by 16 to solve for 'a'.164=a41=a
Write Equation in Vertex Form: Write the equation of the parabola in vertex form using the value of 'a'.Now that we have found a=41, we substitute it back into the equation y=ax2−2.y=(41)x2−2This is the equation of the parabola in vertex form.
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