How do you find the vertex and intercepts for y = 2x^2?

1 Answer
Nov 14, 2015

They are all at (0,0).

Explanation:

Finding the vertex:
Use the formula (-b/(2a), f(-b/(2a))), given the form of the parabola f(x)=ax^2+bx+c. In your case, a=2,b=0 and c=0.
Here, -b/(2a)=-0/(2*2)=0 and f(-b/(2a))=f(0)=2(0)^2=0.
Thus, the vertex is located at (0,0).

Finding the X-intercept:
Plug in 0 for y.
0 = 2x^2=>0=x^2=>0=x
Then plug in 0 for y to determine the point of the intercept. We already know that if we plug in 0 for either point, we will receive 0 as our answer, so the X-intercept is (0,0).

Finding the Y-intercept:
This is very similar to finding the X-intercept, in that we now plug in 0 for x, which we already know will result in the point (0,0).

Alternative method: Graph the parabola and look at the vertex and intercepts.