Chapter 4 - An Introduction to Functions - 4-6 Formalizing Relations and Functions - Practice and Problem-Solving Exercises - Page 273: 46

a(s)=4.5s+10

The relationship of the total amount you spend as a function of the number of pairs of socks you buy can be modeled by the equation a(s)=4.5s+10. I found the slope=4.5 and the y-int=10. This is because as the number of pairs of socks(x-value) increases by one, the amount you spend(y-value) increases by 4.5 and that gives you the slope which is 4.5. The y-intercept is 10 because you only buy one shirt. This gives you the equation a(s)=4.5s+10.