I can't tell if I should use the distance formula or the midpoint . . .

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Landon wrote that 3−2.6=4. which statement about his answer is true?

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?