Line L1 L_1\,L1 passes through the points (2,4)(2, 4)(2,4) and (5,10)(5, 10)(5,10). Line L2 L_2\,L2 passes through the points (−1,3)(-1, 3)(−1,3) and (k,5)(k, 5)(k,5). Line L1 L_1\,L1 and Line L2 L_2\,L2 are perpendicular. Find the value of kkk.