Question

What is the length of MN ?

M
3X
X + 8
634
N
O A. 12
OB. 8
OC. 4
O D. 16

Answer 1

A. 12

Explanation:

Using the Law of Sines,

• sinA / a = sinB / b

Here,

• A = 63°
• a = x + 8
• B = 63°
• b = 3x

Solving :

• sin63°/x + 8 = sin63°/3x
• x + 8 = 3x
• 2x = 8
• x = 4

Finding MN :

• MN = x + 8
• MN = 4 + 8
• MN = 12