Chapter 3 Review
11/11/15
Today I will review for the Chapter 3 test. I'll know I've got it when I can answer the review questions with
80% accuracy.
Homework:
Text p. 204-206 #11-45 odd
Study for tomorrow's Chapter 3 Test
Do Now: While logging into the computer, answer ...
The force F required to stretch a spring varies directly with the amount the
spring is stretched s. Ten pounds of force are needed to stretch a spring 8
inches.
A.) Write a model that relates force F to amount stretched S.
B.) Find the amount the spring is stretched when the
force is 20 pounds.
F=
5
s
4
s = 16 in.
text p. 200-201 # 1-14 answers
2.) f(x) = x - 5
4.) a.)
b.) y = 35x
c.) 280 pages
6.) f(x) = 12x
8.) f(x) = 1/4x + 2
10.) f(n) = 4n - 8; nonproportional because the graph of the line does not pass through
(0,0)
12.) a.) an=1.65n
b.) The relationship is proportional.
14.) Neither is correct. The graph represents f(x) = 3x which is proportional. The table
represents g(x) = 3x - 1 which is not proportional because it does not pass through (0,0).
Chapter 3 Review
Graph Using Table of Values
Determine if an equation is linear
Standard Form
Finding x and y intercepts
Solving Equations Graphically
Finding Slope/Rate of Change
Direct Variation
Arithmetic Sequences
Proportional/Non-proportinal Relationships
Suppose y varies directly as x, and y = -6 when x = 9, find y when x = -3.
y=2
Suppose y varies directly as x, and y = -7 when x = -1, find x when y = 0.
x=0
Find the x-intercept and the y-intercept of the line.
Graph the equation and label the intercepts on the graph.
3y – 4x = 12
x intercept- ( -3, 0)
y intercept- (0, 4)
Move me for the answer!
Solve 3x + 1 = - 2 by graphing. Check your answer
algebraically.
Move me for the answer!
x = -1
Find the root:
1.) 3x + 1 = 2
x = 1/3
2.) 0 = ½x + 3
x = -6
Find the slope.
(10, –7) and (5, –7)
zero slope
(-4,2) and (-2, 10)
m=4
Find the value of y so that the line passing through the two
points has the given slope.
(3, 5) (1, y) m = -2
(-2, y) (0, 3)
y=9
m=
y=4
Find the value of r so the line that passes through each pair of points has the
given slope:
1) (5,2), (-7, r), m= 5/6
r = -8
2) (-4, r), (-8,3), m= -5
r = -17
Determine if the equation is linear. If so, write it in standard form.
1) ½y - 7 = 3x
6x - y = -14
2) -6xy + 2y = 3x
No
Determine if each sequence is an arithmetic sequence. Explain how you know.
1) -2, 2, -4, 4, -6, 6, ...
2) -6, -3, 0, 3, 6, ...
No, common difference isn't the same
Yes, common difference is +3
Write an equation for the nth term of each arithmetic sequence.
1) 3, 3.5, 4, 4.5, ...
2) 1, -1.5, -4, -6.5, ...
an = (1/2)n + (5/2)
*Use your equation to find the 13th term of this sequence.
an = -2.5n + 3.5
a13 = -29
Is the relationship in the chart proportional or nonproportional?
describe the relationship.
Write an equation to
proportional
y = 15x
# of baskets
Donation ($)
1
3
5
7
9
15
45
75
105
135
Is the relationship in the chart a function?
yes, function
At Memorial Hospital, there were 600 births in 1998. In 2000, there
were 550 births. Find the average rate of change in number of
births per year. Explain its meaning.
m = -25 births/year
There was a decrease of 25 births per year.
The electromotive force, E (in volts), varies directly with the current, I (in amperes),
flowing through a given conductor. A current of 4 amperes passing though the
conductor has an electromotive force of 8 volts.
Write a model that relates electromotive force E to current I.
What is the electromotive force if 3 amperes pass through the conductor?
E = 2I
E = 6 volts
The table shows how many points are awarded for answering
consecutive questions on a gameshow.
Question Answered
1
2
3
4
5
Points Awarded
200
400
600
800
1000
1. Does the table of values represent a function? Explain.
Yes
2. Is this a proportional relationship? Explain.
Yes
3. Write an equation for the given data.
4. How many questions were answered if 1800 points were awarded?
P = 200Q
9 questions
f(x) = 3x + 3
f(x) = 5x + 4
f(x) = 9x - 2
no; f(x) = 13x + 13
a=0
b = 33
Write an equation for each graph.
y = 3x
y = -2x + 3
Finished early?
Determine which lesson(s) you need more practice
in.
Go to connected.mcgraw-hill.com and take the selfcheck quiz for that lesson.
Closure
What do you need to study tonight?
Make a plan.