A particle P P\,P moves with constant acceleration (2i−5j)(2\mathbf{i} - 5\mathbf{j})(2i−5j) m s−2^{-2}−2. At time t=0t = 0t=0, P P\,P has speed u u\,u m s−1^{-1}−1. At time t=3t = 3t=3 s, P P\,P has velocity (−6i+j)(-6\mathbf{i} + \mathbf{j})(−6i+j) m s−1^{-1}−1.
Find the value of uuu.