9. For the vectors x=(1,1) and y=(1,-1), determine vector projection of x onto y (5 marks) 10. A line passes through the points A(2,1) and B(-3,5). Write two different vector equations for this line. (4 marks) 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)+1(4,1) (4 marks) 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? (5 marks)