to get the equation of any straight line, we simply need two points off of it, let's use those two points in the picture below.

keeping in mind that for the point-slope form, either point will do, in this case we used the second one, but the first one would have worked just the same.
Answer:
0.004 km; 400 cm; 4000 mm
Step-by-step explanation:
1 km = 1000 m
1 = (1 km)/(1000 m)
4 m * (1 km)/(1000 m) = 4/1000 km = 0.004 km
1 m = 100 cm
1 = (100 cm)/(1 m)
4 m * (100 cm)/(1 m) = 400 cm
1 m = 1000 mm
1 = (1000 mm)/(1 m)
4 m * (1000 mm)/(1 m) = 4000 mm
Answer: 0.004 km; 400 cm; 4000 mm
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