10.A line passes through the points A(2,1) and B(-3,5). Write two different vector equations for this line. 11. Determine the size of the acute angle, to the nearest whole degree, that is created by the intersection of the lines x = 2t, y=1-5t and r=(4,0)+t(−4,1) 12. The lines x-y+1=0 and x+ky-3=0 have an angle of 60° between them. For what values of k is this true?