MTH 157 Week 7 Checkpoint Assignment Due Day 5 Friday - 1 -

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MTH Week 7 Checkpoint Assignment -- Due Day 5 (Friday)

Instructions: In order to complete your checkpoint in an organized and efficient manner, please use this template to type your work and answers.

  • Use the Equation Editor in Microsoft® Word to show your work.
  • Copy and pastecharts and graphs from Microsoft®Excel® into Microsoft®Word.
  • Submit the Microsoft®Word document as an attachment in your individual forum.

Problem / Type your solution here / Please leave this column blank.
Section 13.1 pp. 798-801
# 26 / State whether each equation in Exercises 25–30 represents a linear, quadratic, or exponential function. Tell how you decided.
26. 3x= 5
This is an equation but not a function
(equation has no linear,quadratic or exponential form)
Answer: Equation is not a function
Section 13.1 pp. 798-801
# 28 / State whether each equation in Exercises 25–30 represents a linear, quadratic, or exponential function. Tell how you decided
28. y = 10

Then by definition of exponential function:
Answer:is an exponential function
Section 13.1 pp. 798-801
# 30 / State whether each equation in Exercises 25–30 represents a linear, quadratic, or exponential function. Tell how you decided
30. y = 2x + 23 - 14x

Then by definition of a linear function:
Answer:is a linear function
Section 13.1 pp. 798-801
# 32 / Copy each equation in Exercises 31–33. Replace the boldface italic letter with a number that shows the relationship indicated in the table. Plug x = 1 and y = 0 into equation and solve for b. Then copy each table and complete it by using the corresponding
equation.
32. y = - x + b
If x=1 and y=0 then
0=-1+b
b=1
b =1
Complete Table
X / 1 / 2 / 8 / 10 / 20 / 40
Y / 0 / -1 / -7 / -9 / -19 / -39
Work: y=-x+1
If x=10 then y =-10+1=-9
If x=20 then y=-20+1=-19
If x=40 then y=-40+1=-39
Section 13.1 pp. 798-801
# 42 / For which table(s) of values in Exercises 39–42 is the relationship linear? Tell how you decided. Write the equation for each linear relationship.
X / 5 / 10 / 15 / 20 / 25 / 30
Y / 20 / 30 / 40 / 50 / 50 / 50
Is not a linear function because when x-values are increasing 5 units y value increasing is not constant (from 5 to 15 y values are increasing but from 20 to 25 y-values are constant)
Section 13.1 pp. 798-801
# 46 / The next graph shows the relationship between the number of years (t), that one owns a complete set of collectible baseball cards, from 1971 to 1995, and the value, V, of the set. Note that t= 0 for the year 1971. The equation V = 20 (1.222) also represents this relationship. Use the graph to estimate the answers to Exercises 45–48. See figure on pp 799
46. The value of the set in 1991
Year 1991 then T=20
Using the graph v(20) is between 1000 and 1500 closest to 1000 (1100 approx)
If we want to find exact value: V=20(1.222)20=1102.69
Answer: 1100
Section 13.1 pp. 798-801
# 48 / The next graph shows the relationship between the number of years (t), that one owns a complete set of collectible baseball cards, from 1971 to 1995, and the value, V, of the set. Note that t= 0 for the year 1971. The equation V = 20 (1.222) also represents this relationship. Use the graph to estimate the answers to Exercises 45–48. See figure on pp 799
48. The year when the set is worth $1,500
Work, we can see in the graph that t value wher V(t)=1,500 is greater than 20, 22 approx
Answer: 22 years
Section 13.2 pp. 816-819
# 8 / Give five ordered pairs that make each equation true in Exercises 7 and 8.
  1. y = 20 +
X / 0 / 1 / 2 / 3 / 4
Y / 20 / 61/3 / 62/3 / 21 / 64/3
If x=0 then y=20+0/3=20
If x=1 then y=20+1/3=61/3
If x=2 then y=20+2/3=62/3
If x = 3 then y=20+3/3=21
If x=4 then y020+4/3=64/3
Section 13.2 pp. 816-819
# 12 / Solve each linear equation in Exercises 11–16 using any technique developed in this section. Name the technique. Check.
12. + 6 = - 12
Technique: using properties of equality
Substract 6 from both sides:
3x/4=-12-6
3x/4=-18
Multiply both sides by 4:
3x=-18(4)
3x=-72
Divide both sides by 3
X=-72/3
X=-24
Answer: x=-24
Check: if x=-24 then:

Section 13.2 pp. 816-819
# 22 / Solve each quadratic equation in Exercises 17–22 using any technique you wish. Name the technique. Check.
22.
Work:
Technique : zero product rule

Answer: x=0
Section 13.2 pp. 816-819
# 26 / State the solutions, or estimated solutions, to each quadratic equation in Exercises 23–26 by examining the graph of the related quadratic function. See figure on pp 817
Work:
Using the graph we can see apositive solution between 2 and 2.5 and a negative solution near -1 (at the right)
Answer: 2.3 and -0.8
Section 13.2 pp. 816-819
# 44 / 44. The Political Noise Problem. The amount of background noise is important to television news reporters. One station developed the formula showing the noise level in decibels (N) as it relates to the
time after the speaker stops talking in seconds (t). How many seconds after the speaker stops will the noise level be the greatest? Write and tell how you decided.
WorK: making a table we have:
T=4 then N=86
T=5 then N=89
T=6 then N=90
T=7 then N=89
T=8 then N=86
We see that N is maximum when t=6
Answer: 6 seconds

WEEKLY QUESTION:

Reviewthe NCTM Principles and Standards Web site at Include your response to the following question with your CheckPoint:

What are two standards that relate to the content addressed this week?
Discuss the ways in which this series of problems meets the standards.