If 2000 is placed into a bank account that pays 3% compond interest per year, how much will be in the account after 2 years

Data from 2005 for various age groups show that for each $100 increase in the median weekly income for whites, the median weekly income of blacks increases by $105. also, for workers of ages 25 to 54 the median weekly income for whites was $676 and for blacks was $527. (a) let w represent the median weekly income for whites and b the median weekly income for blacks, and write the equation of the line that gives b as a linear function of w. b = (b) when the median weekly income for whites is $760, what does the equation in (a) predict for the median weekly income for blacks?

(-y to the power of 2 - 4y- to the power of 2 -6 y +3)

Why is partitioning a directed line segment into a ratio of 1: 3 not the same as finding the length of the directed line segment?