Q. A parabola opening up or down has vertex (0,7) and passes through (4,5). Write its equation in vertex form.Simplify any fractions.
Vertex Form of Parabola: 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 (0,7)?Substitute 0 for h and 7 for k in the vertex form.y=a(x−0)2+7y=ax2+7
Use Point to Find 'a': Use the point (4,5) to find the value of 'a'.Replace the variables with (4,5) in the equation.Substitute 4 for x and 5 for y.5=a(4)2+75=16a+7
Solve for 'a': Solve for 'a'.5=16a+7Subtract 7 from both sides.5−7=16a−2=16aDivide both sides by 16.−162=a−81=a
Write Equation with 'a': Write the equation of the parabola with the found value of 'a'.Substitute −81 for a in the equation y=ax2+7.y=(−81)x2+7Vertex form of the parabola: y=−(81)x2+7
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