Checkpoint Assignments
Name: Rebecca L. Mixon Date: 8/4/09
Week - Checkpoint: 8-13.3 and 13.4
Prob. Comments
Page # Problem and Solution (show each step):
# (Grading)
826- 6 The graph of y= -4x+5 is shown on the next page.
828 Use it to find the answers to Exercises 6–8. Check
your work The value of y when x=1
Solution:
Y= -4(1)+5
Y= -4+5
Y= 1
1= -4+5
1= 1
8 The value of x when y = -3
Solution:
-3= -4x+5
-3=4x+5-5 -5-3=4x
2=4x
2=x
-3= -4(2)+5
-3= -8+5
-3=-3
12 5x + 20y = 60
Solution:
5x 20 y 60
5
x + 4y = 12
x=12 y=3
Not sure about this one!!!
26 Use two points on any horizontal line to illustrate
why a horizontal line has a slope of 0.
Solution:
28 The equation shows the total cost for y=12x+5
ordering tickets on the phone for a certain outdoor
concert.
Tickets are $12 each, and there is a one-time
service fee of $5. Can the slope of this line be
thought of as a rate? Explain.
Solution:
32 Write an equation that satisfies the conditions
Parallel to the line y=-4+1
Solution:
36 What happens to the value obtained for the slope if
the coordinates of the two ordered pairs aren’t
subtracted in the same order? Give an example as
part of your explanation.
Solution:
40 The Egg Problem. A certain zoo kept records of
the
relationship between the weight of a mother ostrich
and
the weight of her egg. Data for three birds is shown
in
the next table.
a. Estimate the weight of an egg from a mother
ostrich weighing 175 lbs.
b. How much would you expect the egg to weigh
from a mother ostrich weighing 190 lbs?
Ostrich #1 Ostrich #2 Ostrich #3
Weight of mother 120 lb 160 lb 180 lb
Weight of egg 2.4 lb 3.2 lb 3.6 lb
Solution:
a.
b.
847- 4 find the midpoint of the line segment having the
850 given endpoints.
(8, 1) (2, 9)
Solution:
8 find the other endpoint of a line segment with
the given midpoint and one endpoint
Endpoint: (0,0) midpoint: (4,-3)
Solution:
14 Find the distance between the given points
(-3,-7) (-4,15)
Solution:
28 Find the equations of the lines shown in Exercises
27–29 by using
the slope-intercept method. Be sure to check the
scale of the graph.
I cant copy the graph…don’t worry about this one
30 I cant copy the graph…don’t worry about this one
32 Give the equation of the circle with the given center
and radius in Center at (1, 2); radius = 12
Solution:
42 Sketch the line x=6 How is it related to the line y=6?
Solution:
50 Garden Area Problem. A designer created a
garden from two concentric circles whose equations
are as follows:
(x + 2)2 + ( y - 6)2 = 16 and (x + 2)2 + ( y - 6)2 = 81.
The area between the circles will be covered with
grass. What is the area of that section?
Solution:
52 I cant copy the graph…don’t worry about this one
54 Suppose that someone said that the equation
2 5
connecting points (-1,1) and (2,3) is y x
3 3
This person wants to know whether the line
represented by this equation will contain point (6,9)
Identify two ways by which this person can decide
whether the graph of the equation contains the
point.
Solution:
Chapter 2 Tell whether each quantity in Exercises 1 and 2 is
Review constant or variable.The number of hours in a day
Solution:
6 the total cost of hiring a certain plumber is a
flat rate of $35 plus $9.50/hr. Write an equation that
shows the relationship between the quantities
Solution:
10 Solve each equation in Exercises 10 and 11 by
using the properties of equality. Check.
4x - 18 = 65
Solution:
14 Give the solutions to the following quadratic
equation by examining the graph of the related
quadratic function: Graph:
y x 2 2 x 15.
Equation:
x 2 2 x 15 0
If you can please help if not I cant copy graph
Solution:
18 Find the slope of the line passing through points
(3,11) and (18,20)
Solution:
22 Find the distance between the given points in
(-5,5) and (0,12)
Solution:
26 Give the equation of a line that is parallel
Y=-4x+7
Solution:
30 The graph of an equation in the form y=mx+b is a
straight line. Can the equation of every straight line
be written in the form y=mx+b (Hint: What is the
equation of a vertical line?)
Solution:
34 Give an equation of a line perpendicular to the line
y=4x having the same y-intercept.
Solution:
38 Sketch the graph of a quadratic function for which
the related quadratic equation has only one
solution. Then, sketch one that has two solutions.
Explain how you know by looking at the graph the
number of solutions there are.
Solution: