At the beginning of the month, a song on a streaming service has 1,000 listens, and was getting 38 new listens every day. Meanwhile, a different song already had 900 listens, and was getting 40 new listens each day. Write an equation to show the number of days it would take for the two songs to have the same number of listens. Use x as your variable.

1000 + 38x = 900 + 40x