Factorise completely (2x+1)^2 -(x-1)^2

Using two or more complete sentences, describe how you can find a vector parallel to b=-2,3

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

Which of the functions graphed below has a removable discontinuity?