Answer:
b² = a² + c² - 2ac cos B
Step-by-step explanation:
The cosine rule can be use when you are given three sides of a triangle and ask to find any angle or when you are given two sides and a included angles(the angle between the two sides given) and ask to find the length of a side.
The equation Sophia can use to solve for the side length(b) of a triangle when given two length and the included angle can be expressed below. Sophia was given two sides and an included angle and was asked to find a side length b.
For sides a, b and c the cosine rule can be represented below
a² = b² + c² - 2bc cos A
b² = a² + c² - 2ac cos B
c² = a² + b² - 2ab cos C
The equation required base on your question is
b² = a² + c² - 2ac cos B
B is 0 hope thsi helps and to die lol
-6.6.-5/6.0.6,2/3"""""""""""""""""
Heres oyur answer i hope that can help u
Believ in you self
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The number of points Marco needs to bring his average up to 90% is 15points.
If there's a possible 25 possible points, and Marco has taken 5 quizzes;
Evidently, each quiz has weighs 5 points.
Mathematically;
- 2100 + 500x = 2250 + 450x
x = 3.
Therefore, he needs 5x points = 15 points to bring his average up to 90%.
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https://brainly.in/question/24249798
