we are given
The water level in Ricky lake changes at an average of -7/48 inch for 1 year
It means that
In 1 year , the water level changes at ![\frac{-7}{48} inches](https://tex.z-dn.net/?f=%20%5Cfrac%7B-7%7D%7B48%7D%20inches%20)
and we have to find the water level change after 5 years
so, we can multiply both sides by 5
In 5*1 year , the water level changes at ![5*\frac{-7}{48} inches](https://tex.z-dn.net/?f=%205%2A%5Cfrac%7B-7%7D%7B48%7D%20inches%20)
In 5 years , the water level changes at ![\frac{-35}{48} inches](https://tex.z-dn.net/?f=%20%5Cfrac%7B-35%7D%7B48%7D%20inches%20)
Hence,
the water level change after 5 years is
........Answer
X=4
Y=-0.5
Do you need an explanation?