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Learn how to identify different types of lines, including vertical, horizontal, parallel and perpendicular. Parallel and perpendicular lines Discover the difference between parallel and perpendicular ...

A technician often has to sketch or design ductwork and the other parts of an HVAC system. Sometimes you have to sketch the room or building you are working with. This means working with lines, angles ...

Formal drawings are a more precise style of drawing. They can be produced by hand or with computer aided design (CAD) packages. Formal hand drawings use tools such as rulers and set squares to ensure ...