Q. A parabola opening up or down has vertex (0,−5) and passes through (4,−1). 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,−5)?Since the vertex is (0,−5), we substitute h=0 and k=−5 into the vertex form equation.y=a(x−0)2−5y=ax2−5
Use Point to Find 'a': Use the point (4,−1) to find the value of 'a'.We know the parabola passes through the point (4,−1), so we can substitute x=4 and y=−1 into the equation to solve for 'a'.−1=a(4)2−5−1=16a−5
Solve for 'a': Solve for 'a'.Add 5 to both sides of the equation to isolate the term with 'a'.−1+5=16a−5+54=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 to be 41, we can substitute it back into the equation we derived in Step 2. y=(41)x2−5 This is the equation of the parabola in vertex form.
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