Question

what is the scale factor from the original figure to the scaled copy?

Explanation:

Step1: Define scale - factor formula

The scale factor $k$ from the original to the scaled - copy is given by the ratio of a side - length of the scaled copy to the corresponding side - length of the original. We can use the known side - lengths: original side $a = 10$ and scaled - copy side $a'=5$.
$k=\frac{a'}{a}$

Step2: Calculate the scale factor

Substitute $a = 10$ and $a' = 5$ into the formula.
$k=\frac{5}{10}=\frac{1}{2}=0.5$

Answer:

$0.5$