1. **State the problem:** We need to find the image of triangle $\triangle STU$ after reflecting it over the line $y = 4$. 2. **Reflection formula:** When reflecting a point $(x, y)$ over the horizontal line $y = k$, the image point $(x', y')$ is given by: $$ x' = x $$ $$ y' = 2k - y $$ 3. **Identify the coordinates of points $S$, $T$, and $U$:** From the graph description: - $S = (6, 2)$ - $T = (10, 4)$ - $U = (8, 8)$ 4. **Apply the reflection formula to each vertex:** - For $S(6, 2)$: $$ x'_S = 6 $$ $$ y'_S = 2 \times 4 - 2 = 8 - 2 = 6 $$ - For $T(10, 4)$: $$ x'_T = 10 $$ $$ y'_T = 2 \times 4 - 4 = 8 - 4 = 4 $$ - For $U(8, 8)$: $$ x'_U = 8 $$ $$ y'_U = 2 \times 4 - 8 = 8 - 8 = 0 $$ 5. **Final image coordinates:** - $S' = (6, 6)$ - $T' = (10, 4)$ - $U' = (8, 0)$ 6. **Explanation:** Each point is reflected vertically across the line $y=4$ by measuring the vertical distance from the point to the line and placing the image the same distance on the opposite side. **Answer:** The image of $\triangle STU$ after reflection over $y=4$ has vertices $S'(6,6)$, $T'(10,4)$, and $U'(8,0)$.