Writing Triangle Proofs

Front

What are the three main triangle congruence criteria?

Back

SAS (Side-Angle-Side), SSS (Side-Side-Side), and ASA (Angle-Side-Angle).

Front

Which triangle congruence criterion is NOT valid?

Back

SSA (Side-Side-Angle) is not a valid triangle congruence criterion.

Front

What does the definition of midpoint state?

Back

A midpoint is a point that divides a segment into two equal parts.

Front

What is the definition of an angle bisector?

Back

An angle bisector is a ray that divides an angle into two equal angles.

Front

What is the relationship between congruent angles?

Back

If two angles are congruent, they have the same measure.

Front

What is the significance of the reflexive property in triangle proofs?

Back

The reflexive property states that a quantity is equal to itself, which is often used to show that a side or angle is shared between two triangles.

Front

How do you find the value of x in a triangle problem?

Back

Set up an equation based on the properties of triangles (e.g., angle sum property, congruence criteria) and solve for x.

Front

What is the angle sum property of triangles?

Back

The sum of the interior angles of a triangle is always 180 degrees.

Front

What does it mean for two segments to be congruent?

Back

Two segments are congruent if they have the same length.

Front

What is the definition of vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect; they are always congruent.