To solve the problem, we are given that triangles \( \triangle PQR \sim \triangle ABC \). Since the triangles are similar, corresponding sides are proportional.
1. Understand the Corresponding Sides:
From the diagram, the corresponding sides are:
\( PQ \leftrightarrow AB, \quad QR \leftrightarrow BC, \quad PR \leftrightarrow AC \)
2. Use the Known Values from \( \triangle PQR \):
\( PQ = 3, \quad QR = y, \quad PR = 6 \)
From \( \triangle ABC \): \( AB = z, \quad BC = 4\sqrt{3}, \quad AC = 8 \)
3. Use the Ratio of Hypotenuses:
Since \( PR \) corresponds to \( AC \):
\[ \frac{PR}{AC} = \frac{6}{8} = \frac{3}{4} \]
4. Find Corresponding Sides:
\( PQ \leftrightarrow AB \Rightarrow \frac{PQ}{AB} = \frac{3}{z} = \frac{3}{4} \Rightarrow z = 4 \)
\( QR \leftrightarrow BC \Rightarrow \frac{QR}{BC} = \frac{y}{4\sqrt{3}} = \frac{3}{4} \Rightarrow y = 3\sqrt{3} \)
5. Add \( z + y \):
\[ z + y = 4 + 3\sqrt{3} \]
Final Answer:
The value of \( z + y \) is \( 4 + 3\sqrt{3} \).