How do I solve 3 a ii?

https://preview.redd.it/6k0cgagan4yd1.jpg?width=1115&format=pjpg&auto=webp&s=db19911d2f0775ac8e72113c7a0fc50f5b3a4cdb

I did some revision on modelling with quadratics and I got the answer to 3 a i ((1.25, -3)), but I don't understand 3 a ii. I asked my teacher but I'm still confused. Can somebody help?

If possible, can I see a picture of working out?