501 Geometry Questions

Proving Congruency in Triangles

Now that you understand the basics of congruency, it is time to learn how
to know when two triangles are congruent. There are four different postu-
lates, or tests, that prove congruency in triangles. These postulatesinvesti-
gate the congruencyof corresponding angles and sides of triangles. If two
triangles satisfy any of these four postulates, then they are congruent. Here
are the four tests of congruency:

Test: 1 Side-Side-Side (SSS) Postulate:If three sides of one triangle
are congruent to three sides of another triangle, then the two triangles
are congruent.

Test: 2 Side-Angle-Side (SAS) Postulate:If two sides and the included
angle of one triangle are congruent to the corresponding sides and included
angle of another triangle, then the triangles are congruent.

B

A CS Q

R

“included” angle

B

A CS Q

R

501 Geometry Questions