Help Identifying x-intercepts of quadratic functions

AI Thread Summary
To find the x-intercepts of the quadratic function f(x) = 1/2x^2 - 4, it is not necessary to factor the equation. Instead, set the function equal to zero: 1/2x^2 - 4 = 0. By isolating x^2, you get x^2 = 8, and taking the square root gives x = ±2√2. This method simplifies the process of finding x-intercepts without the need for factoring. Understanding this approach can make solving similar quadratic equations easier.
Kalzar89
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Homework Statement


Identify the vertex and x-intercept(s) of the quadratic function algebraically.



Homework Equations



f(x) = 1/2x^2 - 4

1/2 Is the coefficent if its not clear.



The Attempt at a Solution



Ok I do not need help finding the vertex I have already got that, I need help factoring it out to find the x-intercepts.

Here is my attempt

0 = 1/2x^2 - 4
0 = 1/2 (x^2 - 8)

That is as far as I can factor it, I am terrible at factoring these and I actually have a way easier time factoring trinomials and polynomials.

Could you please explain how I am to factor farther and how am I supposed to solve for the x-intercepts after its all factored. I have even looked all over the internet for a good factoring tutorial guide but I just cannot even understand them.

Thanks
 
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Kalzar89 said:
Ok I do not need help finding the vertex I have already got that, I need help factoring it out to find the x-intercepts.

Here is my attempt

0 = 1/2x^2 - 4
0 = 1/2 (x^2 - 8)

That is as far as I can factor it, I am terrible at factoring these and I actually have a way easier time factoring trinomials and polynomials.

There is no need to worry that much about factoring. You have

\frac{1}{2}x^{2}-4=0.​

Simply solve for x to obtain the intercept.
 
I believe that was what he was trying to do! Kalzar89, there is no need to factor.
(1/2)x^2- 4= 0
(1/2)x^2= 4
x^2= 8
and take the square root of both sides.
x= \pm\sqrt{8}= \pm \sqrt{(4)(2)}= \pm 2\sqrt{2}
 
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