Question

Question 6 of 10

What is the length of the altitude of the equilateral triangle below?
30"
6
6
a
60° 90°
3
60"
3
O
A. 613
O
B. 1
C. 6
Ο Ο O
D. 3
E. 3/5
O
F. 27

Answer 1

The answer is B. 9

Use cosine rule. In this case, I am using SOH and the right triangle:

sin 60°= a ÷ 6 root 3

(6 root 3)(sin 60°)= a

a=9

Explanation: