To plot coordinate points, look at the ordered pair (x, y). The x value moves along the x-axis -- that is, horizontally. If the number is positive, you move to the right, and if it's negative, to the left. The y value moves vertically along the y-axis; if it's positive, move up, and if it's negative, move down. Generally, we move with the x coordinate first.
Using this information, you can either mentally plot each point or work backward to match with the letter. Try it.
You should get these answers:
(-4, -2) A (2, -4) B (4, -2) C (2, 5) D (-1, 1) E (-5, 0) F (4, 2) G (0, -5) H
There are 6 ways we can roll doubles out of a possible 36 rolls (6 x 6), for a probability of 6/36, or 1/6, on any roll of two fair dice. So you have a 16.7% probability of rolling doubles with 2 fair six-sided dice.