In 1992,the life expetency of males was 65.1 years. In 1999, it was 67.5 years. Let E represent the life expetency of in year t and let t represent the number of years since 1992. make this into a linear function E(t)=___t+___
E=mt+b
when t = 0, E = 65.1
so
65.1 = m(0) + b = b
then
E = m t + 65.1
second point
67.5 = m(1999-1992) + 65.1
2.4 = 7m
m = 2.4/7
so
E = (2.4/7) t + 65.1