Answer
Q-86
(a) c(75)=90
c(100)=100
c(105)=105
(b)The total costs of purchasing books
Work Step by Step
Q-86
(a)when x=75
c(x)=x+15
Now substitute the value of x to the above equation
c(x)=75+15
=90
when x=100
c(x)=x
Now substitute the value of x to the above equation
c(x)=100
when x=105
c(x)=x
Now substitute the value of x to the above equation
c(x)=105
(b)The total costs of purchasing books (when the book price is less than 100 and greater than 100).
