A math equation/ word problem solving

Question

The temperature at 4 a.m. Was -13 degrees F. The temperature was rising at a steady rate of 5 degrees F an hour. At what time will the temperature be at 12 Degrees F? 

Answer 1

the temperature has to go from -13 degrees to 12 degrees

this is a difference of 12-(-13)=12+13=25 degrees

25/5=5 hours

4 a.m. plus 5 hours brings you to 9 a.m.

-13+5=-8

-8+5=-3

-3+5=2

2+5=7

7+5=12