Isaac Physics help!

Hi, im really stuck on an isaac physics question and was wondering if anyone could help
its called "running return" and im stuck on part D.
thankyou!

ah okay haha, sorry I didn't realise. here's the link: https://isaacphysics.org/questions/running_return

I've managed to work out the first 3 parts but the last one just confuses me.

I have worked out the time it takes the ball to get from A to B as 1.132.... seconds. And I thought that, because the runner turns around as soon as the ball leaves A, that the Initial velocity would be 0m/s, the acceleration would be 6.9m/s² and the time it would take them would be 1.132... s. but using SUVATs I got the wrong distance for it

How do you use SUVAT equations?

There is a graph in the following thread that may help.
https://www.thestudentroom.co.uk/showthread.php?p=87284146

Ah that graph helped a lot thankyou! I was originally doing the same thing as the other person with the SUVATS.

I got the area under OMN as 6.9t^2 and the area under NQ as [(-6.9 delta t^2 +13.8 t delta t - 6.9t^2)/2) and then added them together. And with delta t as 1.32... the quadratic I ended up with is [6.9t^2] - I solved this to get t= 0.469 or t= -2.734. But I know this is wrong because by working out the area of half OMN (using the positive value of t) you get the maximum displacement as 0.7589 which isn't right. Do you know where I'm going wrong?

Just as I was typing my response, I realised that I had worked out the area of the second triangle wrong and now I know what I did wrong haha. But I managed to get the right answer as 1.5m (I had a few rounding issues with Isaac physics though lol). But thankyou so much - I appreciate all the help!