Answer:
![15\ units](https://img.qammunity.org/2020/formulas/mathematics/middle-school/r7of0iijh2xgemwwf37ybgi99b38o3qlkr.png)
Explanation:
we know that
If two figures are similar, then the ratio of its corresponding sides is equal and the corresponding angles are congruent
In this problem Triangles PQT and RQS are similar by AA Similarity Theorem (The three angles are congruent)
therefore
![(12)/(16)=(x)/(20)\\ \\x=12*20/16\\ \\x=15\ units](https://img.qammunity.org/2020/formulas/mathematics/middle-school/z4pw6ywspdm4d7sy3mwakqr4v0plo0rtx3.png)