The answer is 80.5 ... 805 / 5
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
Answer:
z=-7
Step-by-step explanation:
-9+8*14z+8*2=7*17z+7*8
-9+112z+16=119z+56
112z+7=119z+56
-112z -112z
7=7z+56
-56 -56
-49=7z
:7 :7
z=-7
