15x because the air ballon drops 15 meters each time the elevation decreases
Step-by-step explanation: Im not sure if this is what youre looking for but it drops 15 meters each time, 5 times so the change would be 15x and the x is used as how mant different times the elevation drops
Each time she goes down, she lowers by 15 meters. The integer is 15 and the integer that represents the elevation is x since it isn't explained, and you'd never know the value. I hope this helps.
