Question

Calculate the size of angle x. Give your answer to 1 decimal place. 8 cm 11 cm 15 cm

Answer 1

Answer:

45.6

Step-by-step explanation:

Answer 2

Answer:

45.6° (1 d.p)

Step-by-step explanation:

Using the cosine rule;

c = √( a² + b² - 2ab Cosx)

11 =√(8² + 15² - 2 (8) (15) Cosx)

11² = 8² + 15² - 240 Cosx

11² - 8² - 15² = - 240 Cosx

-168 = -240 cosx

cosx = 0.7

x = cos⁻¹ (0.7) = 45.57 ≈ 45.6°