9514 1404 393
Answer:
Explanation:
The diameter is twice the radius, so ...
XY = 2·ZY
12x -4 = 2(3x +4) . . . . substitute the given expressions
12x -4 = 6x +8 . . . . . . eliminate parentheses
6x = 12 . . . . . . . . . . . . add 4-6x
x = 2
YZ = 3x+4 = 3(2) +4
YZ = 10