Question

Suppose I have a 30, 60, 90 right triangle. The hypotenuse is 10 units long. How long are the other sides?

a) short leg = 5; long leg = 5 √2

b) short and long leg = 5 √2

c) short leg = 5; long leg = 5 √3

d) short leg = 5; long leg =8

Answer 1

c) short leg = 5; long leg = 5 √3

Explanation:

How long are the other sides?

short leg = 5; long leg = 5 √3

Answer 2

option c

Explanation:

The angles are 30° , 60° , 90° . So its a right angled triangle . We can use trigo.

⇒ sin 30 = p/h

⇒ 1/2 = p/10

⇒ p = 10/2

⇒ p = 5

Using Cosine now ,

⇒ cos 30° = b/h

⇒ √3/2 = b/10

⇒ b = √3/2 × 10

⇒ b = 5√3

• Short leg = 5
• Long leg = 5√3

Hence option C is correct.