Answer:
see explanation
Step-by-step explanation:
Since Z is the midpoint of RT , then
RZ = ZT , that is
4x - 30 = 18 ( add 30 to both sides )
4x = 48 ( divide both sides by 4 )
x = 12
Then
RZ = 4x - 30 = 4(12) - 30 = 48 - 30 = 18
RT = RZ + ZT = 18 + 18 = 36
