Combine like terms to create an equivalent expression. Make sure to simplify coefficients and constants as well.
-\dfrac65-\dfrac23v+\dfrac{4}{15}+\ dfrac13v−
5
6
​
−
3
2
​
v+
15
4
​
+
3
1
​
v

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?