Arthur has decided to start saving for a new computer. his money is currently in a piggy bank at home, modeled by the function s(x) = 85. he was told that he could do the laundry for the house and his allowance would be a(x) = 10(x − 1), where x is measured in weeks. explain to arthur how he can create a function that combines the two, and describe any simplification that can be done.

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?