Explanation
In the question, we are given that Simon dilates ST by a scale factor of 5 through center C to produce line segment S'T'.
The dilation, in this case, implies that an enlargement of the pre-image ST has occured. This will then give an image S'T' which is 5 times the pre image.
[tex]\begin{gathered} \therefore\text{ If S'T'=k}\times ST \\ k\text{ would give 5, for the statement to hold} \end{gathered}[/tex]
Answer: 5
