multiply both sides by the reciprical of 5/3 so:
3/5(5/3)w=-10(3/5)
w=-30/5= -6
5 1/4? Im not sure what the question is asking but whatever
Answer:
The distance between them after 30 minutes is 6.5 km.
Step-by-step explanation:
Speed = 
Sarah's speed = 6 km/hr = 1.6667 m/s
Emily's speed = 10 km/hr = 2.7778 m/s
The measure of angle between their bearings = 
After 30 minutes (1800 seconds);
distance = speed x time
Sarah would have covered a distance = 1.6667 x 1800
= 3000 m
= 3 km
Emily would have covered a distance = 2.7778 x 1800
= 5000 m
= 5 km
The distance between them, a, can be determined by applying the cosine rule;
=
+
- 2bcCos A
=
+
-2(5000 x 3000) Cos 105
=
+
-2(5000 x 3000) x (-0.2588)
= 2.5 x
+ 9 x
+ 7764000
= 41764000
a = 
= 6462.5073
a = 6462.5 m
The distance between them after 30 minutes is 6.5 km.
Obviously the 5 apples for $1.00 is the better buy. You are getting more apples for less money.