In 1993 the life expectancy of males in a certain country was 64.6 years. In 1998 it was 67.2 years. Let E represent the life expectancy in year T and let T represent the number of years since 1993. So T is the number of years since 1993. T is 0 in 1993. That means that T has to be 5 in 1998. So in year 1993 or time zero, the life expectancy was 64.6. In 1998 time 5 the life expectancy was 67.2. We now have two points and whenever we have two points we can find a slope. So we're going to do difference of YS over the difference of XS and get .52. Now we know zero 64.6 is really the Y intercept, so we can plug this directly into Y equal MX plus B. So E of T equal .5 two t + 64.6. Now, if we go back and read the directions, the directions specified in the nearest 10th. So we're going to have .5 T plus 64.6, and then it wants to know what happens in 2003. Well, 2003 is 10 years later, so we're going to put 10 in for tea .5 * 10 + 64.6 or 5 + 64.6 for 69.6.