🔍 Key Concepts

• Identify how visible (object) lines are drawn in standard blueprint drafting compared to hidden lines and centerlines. • Look closely at the line styles in the figure: solid, dashed, and dash–dot patterns each have different meanings. • Remember that visible lines represent the actual edges you can see when looking at the object from that view.

💭 Think About

• For each labeled line (A, B, C, D), ask: does this represent an edge you could physically see from that view, or something hidden/imaginary like a center or projection? • Compare the pattern of each labeled line: which ones are continuous thick lines, and which ones are broken or alternating patterns? • Think about the circle in the right-hand view: which part of that drawing shows the real edge of the round hole or cylinder, and which shows its center axis?

✅ Before You Answer

• Confirm which labels point to continuous solid lines (standard for visible/object edges in blueprints). • Verify that hidden lines are shown as short, evenly spaced dashes and should NOT be counted as visible lines. • Verify that centerlines are shown as alternating long and short dashes (dash–dot pattern) and also should NOT be counted as visible lines.