1. The problem asks for the number of line segments on a Tic-Tac-Toe board. 2. A Tic-Tac-Toe board is a 3x3 grid formed by 4 vertical and 4 horizontal lines intersecting. 3. Each intersection point (dot) connects to adjacent dots by line segments. 4. Count the vertical line segments: There are 3 columns of segments, each with 3 segments vertically, so total vertical segments = $3 \times 3 = 9$. 5. Count the horizontal line segments: There are 3 rows of segments, each with 3 segments horizontally, so total horizontal segments = $3 \times 3 = 9$. 6. Total line segments on the board = vertical segments + horizontal segments = $9 + 9 = 18$. 7. Diagonal segments are not part of the grid lines, so they are not counted. Final answer: There are **18** line segments on the Tic-Tac-Toe board.