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suppose a parabola has an axis of symmetry at x = -8, a maximum height of 2, and passes through the point (-7, -1). Write the equation of the parabola in vertex form

User Ptomli
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1 Answer

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Answer:

f(x) = - 3(x + 8)² + 2

Explanation:

f(x) = a(x - h)² + k - the vertex form of the quadratic function with vertex (h, k)

the axis of symmetry at x = -8 means h = -8

the maximum height of 2 means k = 2

So:

f(x) = a(x - (-8))² + 2

f(x) = a(x + 8)² + 2 - the vertex form of the quadratic function with vertex (-8, 2)

The parabola passing through the point (-7, -1) means that if x = -7 then f(x) = -1

so:

-1 = a(-7 + 8)² + 2

-1 -2 = a(1)² + 2 -2

-3 = a

Threfore:

The vertex form of the parabola which has an axis of symmetry at x = -8, a maximum height of 2, and passes through the point (-7, -1) is:

f(x) = -3(x + 8)² + 2

User Nathan Kinsinger
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