Hi, I have the following exercise and I am kind of stuck in the last bit now... There exercise says

"Consider the simple right-angled triangle ABC in the diagram above. The points P, Q, R divide the sides of the triangle in the ratios indicated. Find the coordinates of the points P, Q, R in terms of s, t, u. (Q having 1 and t on each side is only the ratio, it doesn't mean that the length between Q and C is 1)

Well...so far I have Q=(0, t/(t+1)) and R=(1/(1+u), 0)... How do I get P though? Thanks a lot!