Scala join between two RDD

Question
1

Hello,
I’m new in scala, I have two Rdds and I want to perform a join between them. I have to find lat and lon for the tripID. The problem is when I try to perform a join I get an error it’s like it doesn’t recognize a join. Am I missing a library?
I followed the example on https://github.com/rohgar/scala-spark-4/wiki/Pair-RDDs:-Joins

import org.apache.spark.rdd.RDD
def trip(trips: RDD[Trip], stations: RDD[Station]): (Double, Double) = {
val lat = stations.map(x => x.lat)
val lon = stations.map(x => x.lon)
val location = List(lat,lon)
val tripId = 913401
location.join(tripID)
}