Mark and Peter dug ponds in their backyards. Mark’s pond is 4 feet deeper than 3 times Peter’s pond. If Mark’s pond is 19 feet deep, what is the depth of Peter’s pond?
Let’s use p for the number of feet in Mark’s pond
3*p+4=19
3*p=19-4=15
3p=15
p=<<5=5>>5
#### 5