Share
Find the exact value for the perimeter of an equilateral triangle with an altitude of 18 cm
Question
Find the exact value for the perimeter of an equilateral triangle with an altitude of 18 cm
in progress
0
Mathematics
4 years
2021-08-17T14:10:30+00:00
2021-08-17T14:10:30+00:00 1 Answers
12 views
0
Answers ( )
9514 1404 393
Answer:
36√3 cm
Step-by-step explanation:
The perimeter of an equilateral triangle is 2√3 times the height.
P = (2√3)h
P = (2√3)(18 cm) = 36√3 cm
_____
A little more detail
The hypotenuse of a 30°-60°-90° triangle is 2/√3 times the longer leg. Here, the longer leg is 18 cm, so the side length of the equilateral triangle is …
18(2/√3) = 12√3 . . . cm
The equilateral triangle perimeter is 3 times that, or 36√3 cm.