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Find the vertex, the equation of the axis of symmetry, and the y-intercept of each function.

7) y = -2x-4x+5

User Hoot
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1 Answer

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8 votes

Answer:

Vertex: (-1,7)

Equation of the axis of symmetry: x = -1

y-intercept: (0, 5)

Explanation:

I will assume that the function is quadratic where it is supposed to be y = -2x² - 4x + 5.

The standard form of quadratic functions can be written as

y = ax² + bx + c

To find the vertex of this function, we need the axis of symmetry (aos).

aos = - b/2a

= - ( -4/-4)

= - 1

Axis of symmetry: x = -1

For the vertex, simply plug in the aos into the function.

f(x) = -2x² - 4x + 5

f(-1) = -2(-1)² -4(-1) + 5

= -2 + 4 + 5

= 7

Vertex: (-1, 7)

Now the y-intercept is the easiest part, since the function is written in standard form. When it is, the y-intercept is always (0, c), which in this case is (0, 5).

y-intercept: (0,5)

User Spicer
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