Flashcard 07: Unit 05:Triangles

Front

What is the sum of the interior angles of a triangle?

Back

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

Front

What is the relationship between the angles of a triangle and its exterior angle?

Back

The exterior angle of a triangle is equal to the sum of the two opposite interior angles.

Front

How do you find the measure of an unknown angle in a triangle?

Back

To find an unknown angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

What is the definition of an acute triangle?

Back

An acute triangle is a triangle where all three angles are less than 90 degrees.

Front

What is the definition of an obtuse triangle?

Back

An obtuse triangle is a triangle that has one angle greater than 90 degrees.

Front

What is the definition of a right triangle?

Back

A right triangle is a triangle that has one angle equal to 90 degrees.

Front

What is the Triangle Inequality Theorem?

Back

The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

What is the definition of corresponding angles?

Back

Corresponding angles are angles that are in the same position on different parallel lines cut by a transversal.

Front

What is the definition of vertical angles?

Back

Vertical angles are the angles opposite each other when two lines cross. They are always equal.

Front

How do you determine if two triangles are similar?

Back

Two triangles are similar if their corresponding angles are equal and the lengths of their corresponding sides are proportional.