Classifying Triangles

Front

What is a triangle classified by its angles?

Back

Triangles can be classified as acute (all angles < 90°), right (one angle = 90°), or obtuse (one angle > 90°).

Front

What is a triangle classified by its sides?

Back

Triangles can be classified as equilateral (all sides equal), isosceles (two sides equal), or scalene (no sides equal).

Front

What is an acute triangle?

Back

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

Front

What is an obtuse triangle?

Back

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

Front

What is a right triangle?

Back

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

Front

What is an equilateral triangle?

Back

An equilateral triangle is a triangle where all three sides and all three angles are equal (each angle = 60°).

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length.

Front

What is a scalene triangle?

Back

A scalene triangle is a triangle where all three sides are of different lengths.

Front

If the angles of a triangle are x, x, and x, what is the value of x?

Back

Each angle x = 60 degrees.

Front

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

Back

Subtract the sum of the known angles from 180 degrees.