Fig. 7.
To construct an Equilateral Triangle on a given base.
—Let A B ([Fig. 6]) be the given base. From A and B, with radius A B, describe arcs cutting each other in C; join A C and C B, which will complete the required triangle.
To construct a Triangle, the lengths of the Sides being given.
—Let it be required to construct a triangle whose sides shall be equal respectively to 6, 5, and 4. Lay down the base A B ([Fig. 7]), making it equal to 6 divisions of the scale; from A with radius equal to 4 divisions, and from B with radius of 5 divisions of the scale describe arcs cutting each other in C; join A C and C B, which will complete the required triangle.
Fig. 8.
