Q. A parabola opening up or down has vertex (0,−5) and passes through (−8,11). 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)?Substitute 0 for h and −5 for k in the vertex form.y=a(x−0)2+(−5)y=ax2−5
Find 'a' Value: Use the point (−8,11) to find the value of 'a'.Replace the variables with (−8,11) in the equation.Substitute −8 for x and 11 for y.11=a(−8)2−511=64a−5
Solve for 'a': Solve for 'a'.Add 5 to both sides of the equation.11+5=64a16=64aDivide both sides by 64 to solve for 'a'.6416=a41=a
Final Equation: Write the equation of the parabola with the value of 'a'.Substitute 41 for a in the equation y=ax2−5.y=(41)x2−5The vertex form of the parabola is y=(41)x2−5.
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