Equilateral and Isosceles Triangles Flashcard

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 degrees.

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length and the angles opposite those sides are equal.

Front

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

Back

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

Front

If two angles of a triangle are 30 degrees and 60 degrees, what is the measure of the third angle?

Back

The third angle measures 90 degrees, since 180 - (30 + 60) = 90.

Front

In an isosceles triangle, if the equal sides are 5 cm each, what is the maximum possible length of the base?

Back

The maximum possible length of the base is less than 10 cm, according to the triangle inequality theorem.

Front

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

Back

In an equilateral triangle, all angles are equal, each measuring 60 degrees.

Front

How do you find the height of an equilateral triangle?

Back

The height can be found using the formula: height = (√3/2) * side length.

Front

If the base of an isosceles triangle is 8 cm and the equal sides are 5 cm, can this triangle exist?

Back

No, it cannot exist because the sum of the lengths of the two equal sides (5 + 5 = 10) must be greater than the base (8 cm).

Front

What is the formula for the area of a triangle?

Back

The area of a triangle can be calculated using the formula: Area = 1/2 * base * height.

Front

If the angles of a triangle are in the ratio 2:3:4, what are the measures of the angles?

Back

The angles measure 40 degrees, 60 degrees, and 80 degrees.