Kinematics :(

A particle travels in a straight line and decelerates uniformly at 2m/s^2. When t=0 its velocity is u m/s and when t=100 its velocity is -v m/s (where u > v > 0). The average speed of the particle over the 100 seconds is 62.5 m/s. Find the values of u and v.

Okay so this is what I've done so far.

S
U
V: u
A: -2
T: 0

S: 6250
U
V: -v
A: -2
T: 100


D/100= 62.5 therefore d=6250

I did simple suvat for the second but got the wrong answer so I'm assuming thats not the right method.

Any help would be much appreciated!

It'd be better if you worked out the distance it travelled in the 100 seconds span, and then divided that value by 100.

Where di you even get d and D?

Try to model the movement graphically on a graph

Sorry d and D are supposed to the same. I did distance/time=speed. I graphed it but still can’t figure it out

how does your graph look like?

Plus what's the answer?

https://goo.gl/images/Dsq19b Graph looks like this.

U= 150
V= 50

what was your suvat approach?

Literally just subbing in values in s=ut+1/2at^2 and s=vt-1/2at^2

what were the values of U and V that you got??

What was the actual answer?