PLEASE HELP ME PLEASE!!

Mathematics

1 answer:

Anna35 [415]2 years ago

8 0

Step-by-step explanation:

in such a case, where we have all the sides and need angles, the best tool is the extended Pythagoras (for general triangles and not just for right-angled ones) :

c² = a² + b² - 2ab×cos(C)

c is the side opposite of angle C.

the side opposite of B is CA.

so, we have

220² = 100² + 160² - 2×100×160×cos(B)

48,400 = 10,000 + 25,600 - 32,000×cos(B)

12,800 = -32,000×cos(B)

cos(B) = -12,800/32,000 = -0.4

B = 113.5781785...° ≈ 114°

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