quadratic functions

The quadratic function y = (x-4)^2 -3 has a vertex at (4, -3).
The "a" value is 1 so the graph opens up.
The line of symmetry is x=4.
The y-intercept is -3.
The roots are 4+square root of 3, and 4 - square root of 3.

Guest:

(x-4)^2-3

Some of what our guest said is correct and some is not.
Firstly, your expression is not an equaton because it does not have an equal sign.
What do you actually want to do with it. Maybe you just want to simplify it ?
To do this you will need to expand (x-4) ².

(x-4) ²
=(x-4)(x-4)
=x ²-8x+16

So
(x-4) ² - 3
=x ²-8x+16 - 3
=x ²-8x+13

Guest:

The quadratic function y = (x-4)^2 -3 has a vertex at (4, -3). CORRECT
The "a" value is 1 so the graph opens up.
The line of symmetry is x=4. CORRECT
The y-intercept is -3. NOT CORRECT
The roots are 4+square root of 3, and 4 - square root of 3. CORRECT

Thank you for answering. I really like people to get involved.
Now I will take a look at your contribution
It would have been nice if you had explained how you got these answers.

People can't learn from your answers if you don't explain where they come from.
Plus it is hard for me to comment on your errors if you don't show me their origin.