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Graph the parabola y=-x^2Plot 5 pints on the parabola. The vertex, 2 points to the left of the vertex, and 2 points to the right of the vertex.

Graph the parabola y=-x^2Plot 5 pints on the parabola. The vertex, 2 points to the-example-1
User Vilva
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1 Answer

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We have a parabola

y = -x^2

The vertex is at x=0

If x =0, y = 0^2 so y =0 (0,0) is the vertex

Lets pick a point to the right

x=1 y = -1^2 =- 1 so when x=1 y = -1 (1, -1)

Again another point to the right

x=2 y = -2^2 = - 4 so when x=2 y = -4 (2, -4)

We know that the parabola is symmetric across the vertex, but we can prove it

x= -1 y = -( -1) ^2 = -(1) = -1 ( -1,-1)

x = -2 y = -(-2)^2 = -4 ( -2, -4)

Graph the parabola y=-x^2Plot 5 pints on the parabola. The vertex, 2 points to the-example-1
User Danielpiestrak
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2.6k points