A town has a population which is growing linearly. In 1970 its population was 36,000 while in 1985 its population was 63,000. Find a formula for its population P(t), where t=0 corresponds to the year 1970.

Answer 1

do it in thousands
(0, 36) , (15,63)
(y-36)/x = (63-36)/15
You take it from there.