Equilateral and Isosceles Flashcard 2

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

How do you find the measure of an angle in an isosceles triangle?

Back

In an isosceles triangle, the angles opposite the equal sides are equal. If you know one angle, you can find the others using the fact that the sum of angles in a triangle is 180 degrees.

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 is 90 degrees, since 30 + 60 + 90 = 180.

Front

What is the relationship between the sides and angles in a triangle?

Back

In a triangle, the largest angle is opposite the longest side, and the smallest angle is opposite the shortest side.

Front

How do you calculate the height of an equilateral triangle?

Back

The height (h) of an equilateral triangle with side length (a) can be calculated using the formula: h = (√3/2) * a.

Front

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

Back

The area (A) of an isosceles triangle can be calculated using the formula: A = (base * height) / 2.

Front

What is the Pythagorean theorem?

Back

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse (c) is equal to the sum of the squares of the lengths of the other two sides (a and b): c² = a² + b².

Front

If the base of an isosceles triangle is 10 cm and the height is 8 cm, what is the area?

Back

The area is 40 cm², calculated as (10 * 8) / 2.