Constructions

The ancient Greeks constructed geometric shapes using only a straightedge and compass. They didn’t use a ruler with measurements on it, they used a straightedge without measurements.

The compass they used is different to the compass used for finding directions. This compass is used for drawing circles and measuring distances. The word compass comes from an old French word compasser meaning to measure. 

Here is a compass

(insert picture of compass)

The word construction come from a Latin word constructus meaning putting together or building. Constructions are putting together geometric shapes using a straight edge and compass only.

The ancient Greeks were great at geometry. Plato was a philosopher who lived from 427-347 BC. He ran a school with a sign at the entrance that said “Let none ignorant of geometry enter here.” Although he wasn’t a mathematician, he had a lot of influence and mathematicians accepted his belief that geometry should only use a compass and straightedge and never marked measuring tools like a ruler or a protractor. His reason was that these were workman’s tools that were not worthy of a scholar. This meant that the Greeks studied constructions using only these instruments.

We are going to look at various constructions using a compass and straightedge alone.