Page 164 - Algebra 1

Example
5
Application: Reading
A student reads an average of 25 pages per day while reading a 544-page novel. Write a rule in function notation to find the number of pages she has left to read at the end of any given day.
SOLUTION
Let d represent the days spent reading.
25d number of pages read
544 - 25d number of pages that have not been read The number of pages left to read depends on the number of days
the student has been reading. y = 544 - 25d
f(d) = 544 - 25d Use function notation.
Math Reasoning
Write Does it make sense for d to be greater than 21? Explain.
Lesson Practice
a.
(Ex 1)
b.
(Ex 2)
c. d.
(Ex 3)
e.
(Ex 4)
f.
(Ex 5)
Give the domain and range of the relation: (1, 2); (2, 1); (4, 6); (8, 5); (7, 7); (3, 10)
Using a diagram, determine whether the ordered pairs represent a function. {(11, 12); (12, 1); (5, 5); (14, 10); (13, 7)}
Determine whether y = 3x - 1 represents a function.
Use the table. Graph the ordered pairs on a coordinate plane and
determine whether the ordered pairs represent a function.
Printing A brochure costs $0.07 per page to print. Write a rule in function notation to represent the cost of printing c copies of the brochure.
Novelist An author writes 30 pages per day. Write a function rule that the author can use to find how many pages she has left to write before reaching page 400.
x
-1
0
1
-2
0
y
3
0
3
6
6
Practice
Distributed and Integrated
1. Solve 0.3 + 0.05y = 0.65. (24)
2. Verify Verify that the following solutions are correct for each equation given. (19) a. 103 + x = 99 when x = -4
b._1 -x=_3 whenx=-_1 244
*3. Make a table to determine whether y = x + 2 represents a function. (25)
Lesson 25 149