See math question and equation below please help

Question

suppose the growth of populatoin during the period from 1980 to 2008 can be approximated by an equation of the form y=mx+b, where x is the number of years since 1980 and y is the population measured in millions. Find the euqation if two ordered pairs that satisfy it are (0,227) and (10,259)

Answer 1

     To write the equation of a line using y = mx + b, you need to find the slope, m, and the y intercept, b.

The slope formula is change in y/ change in x or subtract the y's/ subtract the x's. m = (259-227)/(10-0) = 32/10 = 3.2.

Nexr, find the y intercept. In this case 227 since (0,227) is on the y axis. Ofter you are given points whic aren't on the y axis and should use the following method to find the y intercept.

y = mx + b, you know the slope is 3.2 so substitute 

y = 3.2x + b    you know that (10,259) must satisfy this for the point to be on the line

259 = 3.2(10)+ b

259 = 32 + b

227 = b

 

ANSWER: y = 3.2 x + 227