Final answer:
To draw line segments and form a shape, Fernanda should use a ruler, as it ensures accuracy in aligning and measuring the lines.
Step-by-step explanation:
Fernanda wants to draw line segments to connect points and form a shape. The most appropriate tool for her to use would be a ruler or a straight edge.
A ruler allows for the drawing of straight lines between points accurately, ensuring that the segments are of precise length and align correctly with the points.
Drawing trend lines on a graph also involves connecting points in the most accurate way to represent data, and a ruler would be beneficial for such tasks as well.
In artistic terms, the line is a basic visual element that can be used to create forms, and in graphical techniques, drawing accurate line diagrams is essential, such as using the head-to-tail method to represent vectors.