Thesaurarium mathematicae, or, The treasury of mathematicks containing variety of usefull practices in arithmetick, geometry, trigonometry, astronomy, geography, navigation and surveying ... to which is annexed a table of 10000 logarithms, log-sines, and log-tangents / by John Taylor.

PROP. II. The Hypothenuse, Base, and one of the Angles Of a Rectangled Triangle given, to find the o∣ther parts thereof.

In the Triangle ABC, the Hypothenuse AC is 871 8/10 parts, the Base AB is 736 parts, and the Angle at B, is known to be a Right-angle; or 90°: First to find the Angle at the Cathetus C, the analogy or proportion holds thus.

As Log. Hypothen: AC 871 8/10 parts* 1.1

To Radius or S. 90°.

So Log. Base AB 736 parts,

To the S. V. at Cathetus C 57° 35'.

Secondly, now having found the Angle at the Cathetus C, to be 57° 35'; I say the Angle of the Base A is 32° 25', being the Compl. of the Angle C, unto 90°.

Thirdly to find the Cathetus BC, this is the ••nalogy, or proportion.

As Radius or S. 90°,

To Log. Hypothen. AC 871 8/10 parts,

So S. V. at Base A 32° 25'.* 1.2

To Log. Cathetus BC, 467 4/10 parts required. It may also be found, as in the former Proposi∣tion.

Notes

• * 1.1

  Fig. 34.
• * 1.2

  Fig. 34.