1. The problem states that triangle ABC was dilated by 50%, creating triangle A'B'C'. 2. Dilation by 50% means the new triangle's sides are 50% of the original triangle's sides. 3. The scale factor for dilation is 0.5 (since 50% = 0.5). 4. The relationship between side AC and side A'C' is given by the formula for dilation: $$A'C' = 0.5 \times AC$$ 5. This means side A'C' is half the length of side AC. 6. Therefore, the correct relationship is $$\frac{1}{2} AC = A'C'$$. 7. This corresponds to option D.