Given:
Consider the below figure attached with this ques.
To find:
The length of the line segment XZ.
Solution:
According to the tangent-secant theorem, the square of tangent is equal to the product of secant and external segment of secant.
Using tangent-secant theorem, we get
[tex]WZ^2=ZX\times ZY[/tex]
[tex](k+4)^2=(k+12)k[/tex]
[tex]k^2+8k+16=k^2+12k[/tex]
[tex]8k+16=12k[/tex]
Subtract both sides by 8k.
[tex]16=12k-8k[/tex]
[tex]16=4k[/tex]
Divide both sides by 4.
[tex]4=k[/tex]
Now,
[tex]XZ=12+k[/tex]
[tex]XZ=12+4[/tex]
[tex]XZ=16[/tex]
Therefore, the measure of XZ is 16 units.