the length of each side of the equilateral triangle is 10 what is the length of altitude h?

Answer 1

The altitude will bisect a 60 degree angle and the 10-unit base of the equilateral triangle as well. The result is a 30-60-90 right-angled triangle with a hypotenuse of 10 units and a short leg of 5 units. From there you can use your knowledge of the special right triangle or the Pythagorean Theorem to find the length of the altitude.