19. -x-2 = 2/3x + 3 5/3 x + 3 = -2 5/3x = -5 x = -3
20. none are correct, you can double check me by plugging in the x and y values in the coordanates into the first problem none of them worked out in the first equasion so no need to test the second
21. -3 is the answer, capable of being done by using desmos