# Right Triangle Rules You've Probably Forgotten

Right triangle rules have applications in various fields. This write-up expounds the various geometric and trigonometric rules of right angled triangles.

Rimlee Bhuyan

Last Updated: Sep 17, 2018

Rules in Geometry

Side-Angle-Side

It states that, if one of the sides of a right angled triangle is congruent with the side of another right angled triangle, then the two triangles are congruent.

Angle-Side-Angle

According to this rule, if one side and an acute angle of a right angled triangle is congruent to the corresponding side and acute angle of another triangle, then the two triangles are congruent.

Angle-Angle-Side

It says, if the hypotenuse of a right angled triangle as well as another angle of the triangle, other than the right angle is congruent to the hypotenuse and angle of another triangle then the two are said to be congruent.

Rules in Trigonometry

*sin*,

*cos*, and

*tan*.