What is the distance between points (9, −7) and (9, 4) on a coordinate plane? enter the answer in the box.

When can u say there is no solution for a system of linear inequalities? explain your answer and show with a system and graph

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?

Last week , donnell practiced the piano 3 hours longer than marcus . together, marcus and donnell practiced the piano 11 hours . for how many hours did each young man practiced the piano