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8 votes
FIND THE VERTEX AND GRAPH THE PARABOLA OF

F(x) = -2X^2 - 8X + 3

(minus 2x squared minus 8x plus 3)

2 Answers

3 votes

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Answer : (-2,11)

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Known that

y = -2x² - 8x + 3

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Way to do + explanation

#First, find the x coordinate first by using the formula of -b/2a

x = -b/2a = -(-8)/2(-2) = 8/-4 = -2

#After getting the x, find the y

y = -2(-2)² - 8(-2) + 3

y = -2×4 +16 + 3

y = -8 + 16 + 3

y = 11

So the vertex is

(-2,11)

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User Sahil Shekhawat
by
5.4k points
10 votes

Answer:

the vertex is (-2, 11)

Explanation:

F(x) = -2X^2 - 8X + 3 can be rewritten as -2(x^2 + 4x) + 3.

We complete the square of x^2 + 4x, obtaining x^2 + 4x + 4 - 4 = (x + 2)^2 - 4

and then we substitute this last result into F(x) = -2(x^2 + 4x) + 3:

F(x) = -2[ (x + 2)^2 - 4 ] + 3, which simplifies to:

F(x) = -2(x + 2)^2 + 8 + 3, or F(x) = -2(x + 2)^2 + 11

Comparing this to the vertex equation (x + h)^2 + k, we see that h must be -2 and k must be 11.

Thus, the vertex is (-2, 11).

User Bernhard Hofmann
by
5.5k points
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