The answer is 18 cm Half of 72 is 36 Since YZ is 30, you would subtract 30 from 36 in order to get XY, so you would get 6 for XY Half of circle W is 24, since it says the diameter of it is 48 So you would subtract XY from half of the diameter of W in order to get WX It would look like this: 24-6=18
