Which equation can be used to find the number of deer in the forest on january 1? a zoologist is recording the loss of deer in a forest. she notes the number of deer, d, in the forest on january 1. one year later, there were 73 deer in the forest, which is 19 fewer deer than were in the forest a year earlier. what is the number of deer in the forest on january 1? a. 73−d=19 b. 73+d=19 c. d−19=73d.  d−73=−19