Question

Find the value of x.

Round to the nearest tenth.
X
16
30°
30
x = [?]
Law of Cosines: c2 = a2 + b2 - 2ab cos C
Please need answer asap

Answer 1

18.0

Explanation:

==>Given:

Triangle with sides, 16, 30, and x, and a measure of an angle corresponding to x = 30°

==>Required:

Value of x to the nearest tenth

==>Solution:

Using the Cosine rule: c² = a² + b² - 2abcos(C)

Let c = x,

a = 16

b = 30

C = 30°

Thus,

c² = 16² + 30² - 2*16*30*cos 30°

c² = 256 + 900 - 960 * 0.8660

c² = 1,156 - 831.36

c² = 324.64

c = √324.64

c = 18.017769

x ≈ 18.0 (rounded to nearest tenth)