Since Beth was born, the population of her town has increased at a rate of 850 people per year. On Beth's 9th birthday, the total population was nearly 307,650, Write and solve a linear equation to find the population on Beth's 16th birthday. I only need the equation pls help

Edit: the equation needs to be in slope intercept form

The survey of study habits and attitudes (ssha) is a psychological test that measures the motivation, attitude toward school, and study habits of students, scores range from 0 to 200. the mean score for u.s. college students is about 115, and the standard deviation is about 30. a teacher who suspects that older students have better attitudes toward school gives the ssha to 55 students who are at least 30 years of age. the mean score is 113.2. assume the population standard deviation is 30 for older students what is the margin of error for a 95% confidence interval for the population mean score for a. older students? b. compute the 95% confidence interval for the population mean score for older students. c. compute the 99% confidence interval for the population mean score for older students. d. compute the 88% confidence interval for the population mean score for older students.