Q. A parabola opening up or down has vertex (0,5) and passes through (−12,−13). Write its equation in vertex form.Simplify any fractions.
Vertex Form: 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 at Vertex: What is the equation of a parabola with a vertex at (0,5)?Substitute 0 for h and 5 for k in the vertex form.y=a(x−0)2+5y=ax2+5
Use Point to Find 'a': Use the point (−12,−13) to find the value of 'a'.Replace the variables with (−12,−13) in the equation.Substitute −12 for x and −13 for y.−13=a(−12)2+5−13=144a+5
Solve for 'a': Solve for 'a'.−13=144a+5Subtract 5 from both sides.−18=144aDivide both sides by 144.a=−18/144a=−1/8
Write Final Equation: Write the equation of the parabola with the found value of 'a'.Substitute −81 for a in the equation y=ax2+5.y=(−81)x2+5Vertex form of the parabola: y=−81x2+5
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