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Please answer this question I need it i. Vertex and standard form.

Please answer this question I need it i. Vertex and standard form.-example-1
User Goodwine
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1 Answer

9 votes

Equation :

This parabola is facing downwards and highest point of the parabola is it's vertex.

Highest point is (-2,2)

so the vertex is (-2,2)

The graph is passing through (-1,0)

Equation in vertex form is


y = a(x - h) {}^(2) + k


0 = a( - 1 + 2) {}^(2) + 2 \\ 0 =a (1) {}^(2) +2 \\ 0 = a + 2 \\ a = - 2

Substitute back in Equation


y = - 2(x + 2) {}^(2) + 2

the graph has two x intercepts -1 and -3

that means (x+1) and (x+3) are the factors

multiply factors to get the equation in standard form


-2(x + 1)(x + 3) = 0 \\ -2(x {}^(2) + x + 3x + 3) = 0 \\ -2( x {}^(2) + 4x + 3) = 0

-2x^2-8x-6=0

User Inbae Jeong
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