Maths help pleaseeeeee

Your solution is fine. (but I'd write (-1,0) and (7,0) rather than leave it as $3\pm 4$) You can verify that by substituting your solutions back in. Though I would suggest making it clear that you know which points are the x-intercepts and which are the y-intercepts.

Thanks but I am not really sure what they have done in the mark scheme e.g.i think they have used quadratic formula

Looks like they expanded then used the quadratic formula. That's pretty unnecessary. You took the quicker, and more sensible route of recognising that it is already in a form you can deal with. ("completed square" form) It's quite surprising they didn't spot it.

But the thing is where have they got the second coordinate from? So the second one in the one ive attached below
Btw i got the first coordinate

Just an alternative ("less simple" form:

$\displaystyle \frac{4 \pm \sqrt{44}} 2 = 2 \pm \frac{\sqrt{44}} 2 = 2 \pm \frac{\sqrt{11 \times 4}} 2 = 2 \pm \frac{\sqrt 4 \times \sqrt{11}} 2 = 2 \pm \frac{2\sqrt{11}} 2 = 2 \pm \sqrt{11}$

The "or" indicates that either is acceptable for the mark, not that it's a second set of solutions.