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A parabola that has a vertex of (3, -2) a focus of (3, -2 1/16) , and opens downward. Which of the following best represents the equation of the parabola in standard form?

2 Answers

0 votes

Answer:

y = –x2 + 6x – 11

Explanation:

plz give brailyest and this one is the actual answer

User Robertly
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3 votes

Answer:


y=-8x^2+48x-74

Explanation:

A parabola that has a vertex of (3, -2) a focus of (3, -2 1/16), then the line of symmetry is x = 3.

The distance between the vertex and focus is equal to p/2, so


(p)/(2)=\sqrt{(3-3)^2+\left(-2+2 (1)/(16)\right)^2}=(1)/(16),

so parabola's equation in vertex form is


(x-x_0)^2=-2p(y-y_0)\\ \\(x-3)^2=-2\cdot (1)/(16)\cdot (y+2)\\ \\(x-3)^2=-(1)/(8)(y+2)\\ \\8(x-3)^2=-(y+2)

In standard form this equation is


8(x^2-6x+9)=-y-2\\ \\y=-8x^2+48x-72-2\\ \\y=-8x^2+48x-74

User Randall
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