Answer: the distance between the points R and T is 45 units.
Step-by-step explanation: We are given to find the distance between the points R and T on the co-ordinate grid.
Distance Formula : The distance between the points (a, b) and (c, d) i given by

From the co-ordinate grid, we note that the co-ordinates of point R are (-30, 10) and the co-ordinates of point T are (15, 10).
Therefore, the distance between the points R and T is given by

Thus, the distance bewteen the points R and T is 45 units.