4-6 -- Isosceles and Equilateral Triangles

Front

What is an equilateral triangle?

Back

An equilateral triangle is a triangle in which all three sides are of equal length and all three angles are equal, each measuring 60°.

Front

What is the perimeter of an equilateral triangle with side length 's'?

Back

The perimeter of an equilateral triangle is given by the formula: Perimeter = 3s.

Front

If an isosceles triangle has two equal sides of length 'a' and a base of length 'b', what is the formula for its perimeter?

Back

The perimeter of an isosceles triangle is given by the formula: Perimeter = 2a + b.

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°.

Front

In an isosceles triangle, if the base angles are equal, how can you find the vertex angle?

Back

If the base angles are each 'x', then the vertex angle can be found using the formula: Vertex angle = 180° - 2x.

Front

What is the relationship between the angles in an equilateral triangle?

Back

In an equilateral triangle, all angles are equal and each measures 60°.

Front

If one angle of an isosceles triangle measures 40°, what is the measure of the other two angles?

Back

The other two angles each measure 70° because the sum of the angles must equal 180°.

Front

What is the measure of each angle in an equilateral triangle with a perimeter of 72?

Back

Each angle measures 60° because all angles in an equilateral triangle are equal.

Front

How do you find the height of an equilateral triangle?

Back

The height 'h' can be found using the formula: h = (sqrt(3)/2) * s, where 's' is the length of a side.

Front

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

Back

The area 'A' of an equilateral triangle is given by the formula: A = (sqrt(3)/4) * s^2.