Which sketch method is designed to measure an item using two fixed points forming a triangle?

• A. Coordinate method
• B. Triangulation method
• C. Cross projection method
• D. Oblique projection method

Answer: (B)

Triangulation relies on a known baseline formed by two fixed points. By sighting the item from both points, you create a triangle where the two fixed points are the base and the lines to the item form the other sides. With the baseline length known and the viewing angles (or distances) measured, you can use straightforward geometry to determine the size or position of the item. This makes triangulation the method designed specifically for measuring an item using two fixed points that establish a triangle.

In contrast, a coordinate method uses a grid or coordinate system rather than a triangle formed by two fixed points; cross projection and oblique projection are projection techniques used in drawing, not methods built around measuring an item via a baseline triangle.