A level maths: coordinate geometry of circles?

[Hello]

I am revising coordinate geometry for my maths mock this week.
I worked out a question on the line that intersects the circle. I got the coordinates to be 9,-2 and 1,2 but it says in the answers this is wrong. Can someone explain to me what i did wrong? This is my working https://twitter.com/hellojessiej/status/...4929765376 (i uploaded it to an old twitter account i made years ago). On the photo i wrote the question too. Can you explain where i have gone wrong please, and how i'd do it right?

[Amy]

4x5x0 = 0
But you don't go on to actually use the quadratic formula, so this mistake becomes irrelevant.

y^2 - 4y does not equal (y+2)(y-2). That would be y^2 - 4.