Answer:
We have the following theorem:
If <em>f </em>is a quadratic function of the form and , then the function <em>f </em>has two x-intercepts.
(a)
For this function a = -8 and c = -2, then is greater than zero. Therefore, we cannot conclude anything.
(b)
For this function a = -8 and we don't know the value of c. Therefore, we cannot conclude anything.
(c)
For this function a = 8 and c = -7, then is less than zero. Therefore, we can conclude that the function <em>k </em>has two x-intercepts.
(d)
For this function a = and c = 210, then is less than zero. Therefore, we can conclude that the function <em>k </em>has two x-intercepts.
(e)
For this function a = 4 and c = 7, then is greater than zero. Therefore, we cannot conclude anything.
(f)
We cannot conclude anything because this is not a quadratic function.