Isosceles Triangles

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 the property of the angles in an isosceles triangle?

Back

The angles opposite the equal sides of an isosceles triangle are also equal.

Front

How do you find the base angles of an isosceles triangle if the vertex angle is known?

Back

The base angles can be found using the formula: Base Angle = (180° - Vertex Angle) / 2.

Front

If two angles of a triangle are equal, what type of triangle is it?

Back

It is an isosceles triangle.

Front

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

Back

The sum of the interior angles of any triangle is always 180°.

Front

In an isosceles triangle, if the equal sides are 10 cm each and the base is 8 cm, how can you find the height?

Back

You can use the Pythagorean theorem to find the height by dropping a perpendicular from the vertex to the base, creating two right triangles.

Front

What is the formula for the area of an isosceles triangle?

Back

Area = (base * height) / 2.

Front

If the base angles of an isosceles triangle are 50°, what is the vertex angle?

Back

The vertex angle is 80° (180° - 50° - 50°).

Front

How do you determine if a triangle is isosceles using side lengths?

Back

If two sides of a triangle are of equal length, then the triangle is isosceles.

Front

What is the relationship between the sides and angles in an isosceles triangle?

Back

In an isosceles triangle, the sides opposite the equal angles are equal in length.