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Finding y intercepts and x intercepts of the graph of the function

Finding y intercepts and x intercepts of the graph of the function-example-1
User DChimento
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1 Answer

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We have the next function


f(x)=-2x^3+10x^2+48x

And we must find its x-intercepts and y-intercepts

1. y-intercepts:

To find the y-intercepts we need to replace x = 0 in the function and then solve it for y

So, replacing x = 0 in the function we obtain


\begin{gathered} y=-2(0)^3+10(0)^2+48(0) \\ y=0+0+0 \\ y=0 \end{gathered}

That means, the y-intercept of the function is 0.

2. x-intercepts:

To find the y-intercepts we need to replace y = 0 in the function and then solve it for x

So, replacing y = 0 in the function we obtain


0=-2x^3+10x^2+48x

Now, we must solve it for x:

1. we must extract the common factor -2x


0=-2x(x^2-5x-24)

2. we must factor the polynomial inside the parentheses


0=-2x(x-8)(x+3)

3. We must divide both sides by -2


0=x(x-8)(x+3)

We can see that the values for x that satisfy the equality are 0, 8 and -3

That means, the x-intercepts of the function are 0, 8 and -3.

ANSWER:

y-intercept(s): 0

x-intercept(s): 0, 8, -3

User Mandoleen
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