Equilateral and Isosceles Triangle

Front

What is an equilateral triangle?

Back

A triangle where all three sides are equal in length and all three angles measure 60 degrees.

Front

What is an isosceles triangle?

Back

A triangle with at least two sides of equal length and the angles opposite those sides are also equal.

Front

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

Back

180 degrees.

Front

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

Back

It is an isosceles triangle.

Front

What do the angles in an equilateral triangle measure?

Back

60 degrees each.

Front

In an isosceles triangle, if one angle measures 40 degrees, what do the other two angles measure?

Back

70 degrees each.

Front

What is the base of an isosceles triangle?

Back

The side that is not equal in length to the other two sides.

Front

How do you find the height of an equilateral triangle?

Back

Use the formula: height = (sqrt(3)/2) * side length.

Front

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

Back

The angles opposite the equal sides are congruent.

Front

What is the formula for the area of a triangle?

Back

Area = 1/2 * base * height.