The answer is the third one
You have to distribute the 7 to x and 2 so :
7x+14=2x-1
Add one to both sides (inverse operations)
7x+14=2x-1
+1 +1
7x+15=2x
Cross Cancel by subtracting 7x from both sides
7x+15=2x
-7x -7x
15=-5x
Divide by -5
15/-5= -5/-5
X= -3
What do u mean a reasonable value of the range range is used when there are 2 numbers not in a sentence