Creating a 15° line with drafting triangles A 15° line can be produced by combining the standard 45° triangle with the 30°/60° triangle. Evaluate this statement.

Introduction / Context: Traditional drafting uses fixed-angle triangles (45° and 30°/60°) with a T-square or straightedge to construct common angles. Combining these aids enables many additional angles without a protractor.

Given Data / Assumptions:

• A 45°-45°-90° triangle and a 30°-60°-90° triangle are available.
• Triangles can be stacked or used against a straightedge without slipping.
• Desired output is a 15° line relative to a reference horizontal.

Concept / Approach: Using angle subtraction: 45° - 30° = 15°. By orienting one triangle against the other, the composite angle between a triangle edge and the baseline becomes 15°, allowing accurate construction of that angle.

Step-by-Step Solution:

Verification / Alternative check: Many drafting texts list standard composite angles achievable with triangles, including 15°, 75°, and others derived from sums/differences of 30°, 45°, and 60°.

Why Other Options Are Wrong: “Incorrect” would suggest the triangles are limited to only their nominal angles; in practice their combination yields additional precise angles.

Common Pitfalls: Slippage between triangles leading to angle error; misidentifying the 30° versus 60° side; forgetting to keep one edge firmly against the baseline.

Final Answer: Correct