law of sines

Angle-side ratio rule

The law of sines is a formula relating the sides of a triangle to the sines of their opposite angles: each side divided by the sine of its opposite angle equals the same constant.

It allows solving triangles when you know some combination of sides and angles but not all: Using the law of sines, we found the missing angle was 47 degrees.

triangles

opposite side

Facing or contrary position

obtuse triangle · ASA · SSA · vertex · sides · angles · altitude · circumradius · area formula · proportionality

formula

ratio

Comparative numerical relation

rearrangement · derivation · proof · equation · sin · arcsin · calculation · algebraic manipulation · approximation

applications

surveying

Measuring and charting terrain

angle of elevation · astronomy · cartography · engineering · architecture · physics · bearing

related-theorems

Pythagorean theorem

Relates right triangle sides

Categories
Opposites
trigonometric function used in triangle laws

law of sineslaw of cosines

Triangle side-angle relation

Pythagorean theorem

Family

law, laws, law of cosines, tangent, sine, cosine, sinusoid, sinusoidal, sines

Familiarity
Top 200,000
Profile
Used worldwide · Timeless · Abstract · Rated G