3Constructing triangles Aim: To construct triangles using a protractor.60º
4Draw a triangle with one side 6cm and angles at each end of 30º and 70º. Mark 70ºMark 30º6 cm
5Draw a triangle with a side 12 cm and side 9 cm with an angle of 75º between them.Mark 75º12 cm
6Three ways to construct triangles. When constructing triangle we need a combination of angles of lengths.We can construct triangles with a compass if we have the lengths of the 3 sides (S S S).We can construct triangle using a protractor if we have the length of 1 side and the measurement of 2 angles ( A S A ).We can construct triangle using a protractor if we have the length of 2 sides and the measurement of 1 angles ( S A S ).Note: To construct triangles, we need to know the length of at least 1 side plus 2 other pieces of information.
7Task and HomeworkConstruct the following triangle:S S S Triangles5cm 7cm 9cm6cm 6 cm 4cm10cm 8cm 7cm6cm 8cm 10cm7cm 7 cm 7 cmA S A Triangles40º 7cm 50º45º 6 cm 45º20º 8cm 100º60º 8cm 60º110º 7 cm ºA S A Triangles7cm 50º 4 cm6 cm 45º 6 cm8cm 100º 6 cm8cm 60º 8 cm7 cm º 6 cm