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2age 3:Find the vertex and the intercepts of the graph of the function.f (x) = (x + 2)2 – 9Do not enter any spaces in the answers.3The vertex isage 4:AEnter the x-intercepts as two points separated by a comma. Do not enter any spacds.A/ge 5:The y-intercept is the pointA/ge 6:Previous Page1Next PagePage 10 of 35Help ASAP no links

2age 3:Find the vertex and the intercepts of the graph of the function.f (x) = (x-example-1
User John Lucas
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1 Answer

1 vote

Answer:

Vertex = (-2, - 9)

X- intercept: (-5, 0), (1, 0)

y-intercept: (0, -5)

Step-by-step explanation:

If we have a quadratic equation of the form


y=(x-k)^2+h

then the vertex is given by


\text{vertex}=(k,h)

Now, in our case we have


y=(x+2)^2-9

meaning k = -2 and h = - 9; therefore, the vertex is at


vertex=(-2,9)

The intercepts of the parabola are the points where it intersects the x-axis. This happens when y = 0.

Putting in y = 0 in the equation for the parabola gives


0=(x+2)^2-9

adding 9 to both sides gives


(x+2)^2=9

taking the square root of both sides gives


\sqrt[]{(x+2)^2}=\sqrt[]{9}


x+2=\pm3

subtracting 2 from both sides gives


x=\pm3-2

which gives us two solutions


\begin{gathered} x=-3-2=-5 \\ x=3-2=1 \end{gathered}

Hence, the x-intercepts of the parabola are at


\begin{gathered} (-5,0) \\ (1,0) \end{gathered}

Now, we find the y-intercept.

The y-intercept is the point at which the parabola intersects the y-axis.

This happens when x = 0.

Putting in x = 0 in the equation for the parabola gives


\begin{gathered} y=(x+2)^2-9 \\ y=(0+2)^2-9 \\ y=4-9 \\ \boxed{y=-5} \end{gathered}

Hence, the y-intercept is at


(0,-5)

To summarize our results,

Vertex = (-2, - 9)

X- intercept: (-5, 0), (1, 0)

y-intercept: (0, -5)

User Yoshitaka
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3.4k points