
William W. answered 10/21/20
Experienced Tutor and Retired Engineer
If M is the midpoint then, by the definition of a midpoint, the two segments RM and MS are the same.
So x + 3 must equal 2x - 1
x + 3 = 2x - 1 [subtract "x" from both sides to get:
3 = x - 1 [add 1 to each side to get:
x = 4
If x = 4 then, because RM = x + 3, we can say RM = 4 + 3 or RM = 7