Question 1

Suppose $f$ is a linear function with $f ( 8 ) = 22.64$ . If the slope of $f$ is 2.08, what value of $x$ gives $f ( x ) = 13$ ?

Accepted Answer

A)  $x =$ 34 
B)  $x =$3.37 
C)  $x =$33.04 
D)  $x =$3.54

Question 2

Solve the equation $10 x - 2 y = 5$ for $y$ .

Accepted Answer

A)  $y = \frac { 5 - 10 x } { 2 }$ or $y = 2.5 - 5 x$ 
B)  $y = \frac { 5 + 10 x } { 2 }$ or $y = 2.5 + 5 x$ 
C)  $y = \frac { 10 x - 5 } { 2 }$ or $y = 5 x - 2.5$ 
D)  None of the above.

Question 3

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.09 D$ .
If I decide to buy $38 more in merchandise, how much additional sales tax will I have to pay?

Accepted Answer

A)  $3.42 
B)  $3.91 
C)  $0.81 
D)  $0.09

Question 4

The following table shows the depth D , in inches, of water in a pond after $d$ days of eva- poration. Find a linear model for depth as a function of days. $$\begin{array} { | l | l | l | l | l | } 
\hline d & 4 & 6 & 8 & 10 \
\hline D & 779 & 777 & 775 & 773 \
\hline
\end{array}$$

Accepted Answer

A)  $D = - 2 d + 787$ 
B)  $D = 783 d + - 1$ 
C)  $D = - 1 d + 783$ 
D)  $D = 787 d + - 2$

Question 5

The following table shows the number C , in millions, of cars sold in the U.S.  years after 2005. Use the regression line for the data to estimate the number of cars sold in 2013.

Accepted Answer

A)  $3.37$ million 
B)  $4.51$ million 
C)  $3.16$ million 
D)  $4.11$ million

Question 6

Solve the equation $11.59 x - 8.34 y = 11.51$ for $y$ .

Accepted Answer

A)  $y = \frac { 11.51 - 11.59 x } { 8.34 }$ or $y = 1.38 - 1.39 x$ 
B)  $y = \frac { 11.51 + 11.59 x } { 8.34 }$ or $y = 1.38 + 1.39 x$ 
C)  $y = \frac { 11.59 x - 11.51 } { 8.34 }$ or $y = 1.39 x - 1.38$ 
D)  None of the above.

Question 7

At a distance 4 miles west of town, oil-bearing deposits are found 3231 feet deep. Also, 6 miles west of town, the oil is found 3416 feet down. Assuming the oil-bearing stratum lies on a straight line,
How deep would you expect to drill 8 miles west of town in order to find oil?

Accepted Answer

A)  3416 feet 
B)  3416.1 feet 
C)  3601.17 feet 
D)  3601 feet

Question 8

We have $18.54 to spend on vegetable plants for our garden. Tomato plants cost $0.81 each, and pepper plants cost $0.36 each. There is space in the garden for 29 plants.
How many of each are bought?

Accepted Answer

A)  15 tomatoes and 14 peppers 
B)  11 tomatoes and 18 peppers 
C)  14 tomatoes and 15 peppers 
D)  18 tomatoes and 11 peppers

Question 9

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.08 D$ .
If I decide to buy $35 more in merchandise, how much additional sales tax will I have to pay?

Accepted Answer

A)  $2.8 
B)  $3.04 
C)  $0.6 
D)  $0.08

Question 10

For a certain line, a run of 3 feet corresponds to a rise of 8 feet. What is the slope of this line?

Accepted Answer

A)  2.67 feet 
B)  0.38 feet 
C)  0.65 feet 
D)  2.78 feet

Question 11

We have $12.26 to spend on vegetable plants for our garden. Tomato plants cost $0.83 each, and pepper plants cost $0.33 each. There is space in the garden for 22 plants.
How many of each are bought?

Accepted Answer

A)  8 tomatoes and 14 peppers 
B)  12 tomatoes and 10 peppers 
C)  14 tomatoes and 8 peppers 
D)   15 tomatoes and 16 peppers

Question 12

The following table shows the money M left in your cookie jar after $\mathrm { W }$ withdrawals from the jar. Find a linear model for M in terms of W. $$\begin{array} { | l | l | l | l | l | } 
\hline x & 3 & 4 & 5 & 6 \
\hline y & 136 & 121 & 106 & 91 \
\hline
\end{array}$$

Accepted Answer

A)  $M = 136 w - 15$ 
B)  $M = 181 w - 15$ 
C)  $M = - 15 w + 136$ 
D)  $M = - 15 w + 181$

Question 13

The following table shows the running speed  , in centimeters per second, of ants as a func- tion of the temperature $T$ in degrees Celsius. Use linear regression to model running speed as a function of
Temperature.

Accepted Answer

A)  $R = 0.06 T + 2.74$ 
B)  $T = 0.06 R + 2.74$ 
C)  $R = 0.24 T - 3.58$ 
D)  $T = 0.24 R - 3.58$

Question 14

Suppose $f$ is a linear function with $f ( 7 ) = 22.69$ and $f ( 11 ) = 33.37$ . Find an equation for $f$ .

Accepted Answer

A)  $f ( x ) = 0.37 x + 22.69$ 
B)  $f ( x ) = 22.69 x + 0.37$ 
C)  $f ( x ) = 2.67 x + 4$ 
D)  $f ( x ) = 4 x + 2.67$

Question 15

The following table shows the money M left in your cookie jar after $\mathrm { W }$ withdrawals from the jar. Find a linear model for M in terms of W.

Accepted Answer

A)  $M = 139 w - 16$ 
B)  $M = 155 w - 16$ 
C)  $M = - 16 w + 139$ 
D)  $M = - 16 w + 155$

Question 16

The following table shows the depth D , in inches, of water in a pond after $d$ days of eva- poration. Find a linear model for depth as a function of days.

Accepted Answer

A)  $D = - 2 d + 769$ 
B)  $D = 763.67 d + - 0.67$ 
C)  $D = - 0.67 d + 763.67$ 
D)  $D = 769 d + - 2$

Question 17

Suppose $f$ is a linear function with $f ( 6 ) = 20.98$ and $f ( 10 ) = 30.3$ . Find an equation for $f$ .

Accepted Answer

A)  $f ( x ) = 0.43 x + 20.98$ 
B)  $f ( x ) = 20.98 x + 0.43$ 
C)  $f ( x ) = 2.33 x + 7$ 
D)  $f ( x ) = 7 x + 2.33$

Question 18

We have $18.33 to spend on vegetable plants for our garden. Tomato plants cost $0.87 each, and pepper plants cost $0.33 each. There is space in the garden for 31 plants.
How many of each are bought?

Accepted Answer

A)  13 tomatoes and 18 peppers 
B)  16 tomatoes and 15 peppers 
C)  18 tomatoes and 13 peppers 
D)  15 tomatoes and 16 peppers

Question 19

The following table shows the gross national product G , in trillions of dollars,  years after 2005. Use linear regression to model G as a function of  .

Accepted Answer

A)  $\quad G = 13.01 t + 0.35$ 
B)  $G = 0.35 t + 13.01$ 
C)  $G = 0.35 t + 12.79$ 
D)  $G = 0.76 t + 12.79$

Question 20

The following table shows the money M left in your cookie jar after $\mathrm { W }$ withdrawals from the jar. Find a linear model for M in terms of W. $$\begin{array} { | l | l | l | l | l | } 
\hline x & 4 & 5 & 6 & 7 \
\hline y & 134 & 118 & 102 & 86 \
\hline
\end{array}$$

Accepted Answer

A)  $M = 134 w - 16$ 
B)  $M = 198 w - 16$ 
C)  $M = - 16 w + 134$ 
D)  $M = - 16 w + 198$

Exam 3: Straight Lines and Linear Functions

Suppose $f$ is a linear function with $f ( 8 ) = 22.64$ . If the slope of $f$ is 2.08, what value of $x$ gives $f ( x ) = 13$ ?

Solve the equation $10 x - 2 y = 5$ for $y$ .

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.09 D$ . If I decide to buy $38 more in merchandise, how much additional sales tax will I have to pay?

The following table shows the depth D , in inches, of water in a pond after $d$ days of eva- poration. Find a linear model for depth as a function of days. $\begin{array} { | l | l | l | l | l | } \hline d & 4 & 6 & 8 & 10 \\\hline D & 779 & 777 & 775 & 773 \\\hline\end{array}$

The following table shows the number C , in millions, of cars sold in the U.S. years after 2005. Use the regression line for the data to estimate the number of cars sold in 2013.

Solve the equation $11.59 x - 8.34 y = 11.51$ for $y$ .

At a distance 4 miles west of town, oil-bearing deposits are found 3231 feet deep. Also, 6 miles west of town, the oil is found 3416 feet down. Assuming the oil-bearing stratum lies on a straight line, How deep would you expect to drill 8 miles west of town in order to find oil?

We have $18.54 to spend on vegetable plants for our garden. Tomato plants cost $0.81 each, and pepper plants cost $0.36 each. There is space in the garden for 29 plants. How many of each are bought?

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.08 D$ . If I decide to buy $35 more in merchandise, how much additional sales tax will I have to pay?

For a certain line, a run of 3 feet corresponds to a rise of 8 feet. What is the slope of this line?

We have $12.26 to spend on vegetable plants for our garden. Tomato plants cost $0.83 each, and pepper plants cost $0.33 each. There is space in the garden for 22 plants. How many of each are bought?

The following table shows the money M left in your cookie jar after $\mathrm { W }$ withdrawals from the jar. Find a linear model for M in terms of W. $\begin{array} { | l | l | l | l | l | } \hline x & 3 & 4 & 5 & 6 \\\hline y & 136 & 121 & 106 & 91 \\\hline\end{array}$

The following table shows the running speed , in centimeters per second, of ants as a func- tion of the temperature $T$ in degrees Celsius. Use linear regression to model running speed as a function of Temperature.

Suppose $f$ is a linear function with $f ( 7 ) = 22.69$ and $f ( 11 ) = 33.37$ . Find an equation for $f$ .

The following table shows the depth D , in inches, of water in a pond after $d$ days of eva- poration. Find a linear model for depth as a function of days.

Suppose $f$ is a linear function with $f ( 6 ) = 20.98$ and $f ( 10 ) = 30.3$ . Find an equation for $f$ .

We have $18.33 to spend on vegetable plants for our garden. Tomato plants cost $0.87 each, and pepper plants cost $0.33 each. There is space in the garden for 31 plants. How many of each are bought?

The following table shows the money M left in your cookie jar after $\mathrm { W }$ withdrawals from the jar. Find a linear model for M in terms of W. $\begin{array} { | l | l | l | l | l | } \hline x & 4 & 5 & 6 & 7 \\\hline y & 134 & 118 & 102 & 86 \\\hline\end{array}$

Exam 3: Straight Lines and Linear Functions

Suppose fff is a linear function with f(8) =22.64f ( 8 ) = 22.64f(8) =22.64 . If the slope of fff is 2.08, what value of xxx gives f(x) =13f ( x ) = 13f(x) =13 ?

Solve the equation 10x−2y=510 x - 2 y = 510x−2y=5 for yyy .

The sales tax TTT , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by T=0.09DT = 0.09 DT=0.09D . If I decide to buy $38 more in merchandise, how much additional sales tax will I have to pay?

The following table shows the number C , in millions, of cars sold in the U.S. years after 2005. Use the regression line for the data to estimate the number of cars sold in 2013.

Solve the equation 11.59x−8.34y=11.5111.59 x - 8.34 y = 11.5111.59x−8.34y=11.51 for yyy .

At a distance 4 miles west of town, oil-bearing deposits are found 3231 feet deep. Also, 6 miles west of town, the oil is found 3416 feet down. Assuming the oil-bearing stratum lies on a straight line, How deep would you expect to drill 8 miles west of town in order to find oil?

We have $18.54 to spend on vegetable plants for our garden. Tomato plants cost $0.81 each, and pepper plants cost $0.36 each. There is space in the garden for 29 plants. How many of each are bought?

The sales tax TTT , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by T=0.08DT = 0.08 DT=0.08D . If I decide to buy $35 more in merchandise, how much additional sales tax will I have to pay?

For a certain line, a run of 3 feet corresponds to a rise of 8 feet. What is the slope of this line?

We have $12.26 to spend on vegetable plants for our garden. Tomato plants cost $0.83 each, and pepper plants cost $0.33 each. There is space in the garden for 22 plants. How many of each are bought?

The following table shows the running speed , in centimeters per second, of ants as a func- tion of the temperature TTT in degrees Celsius. Use linear regression to model running speed as a function of Temperature.

Suppose fff is a linear function with f(7) =22.69f ( 7 ) = 22.69f(7) =22.69 and f(11) =33.37f ( 11 ) = 33.37f(11) =33.37 . Find an equation for fff .

The following table shows the money M left in your cookie jar after W\mathrm { W }W withdrawals from the jar. Find a linear model for M in terms of W.

The following table shows the depth D , in inches, of water in a pond after ddd days of eva- poration. Find a linear model for depth as a function of days.

Suppose fff is a linear function with f(6) =20.98f ( 6 ) = 20.98f(6) =20.98 and f(10) =30.3f ( 10 ) = 30.3f(10) =30.3 . Find an equation for fff .

We have $18.33 to spend on vegetable plants for our garden. Tomato plants cost $0.87 each, and pepper plants cost $0.33 each. There is space in the garden for 31 plants. How many of each are bought?

The following table shows the gross national product G , in trillions of dollars, years after 2005. Use linear regression to model G as a function of .

Suppose $f$ is a linear function with $f ( 8 ) = 22.64$ . If the slope of $f$ is 2.08, what value of $x$ gives $f ( x ) = 13$ ?

Solve the equation $10 x - 2 y = 5$ for $y$ .

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.09 D$ . If I decide to buy $38 more in merchandise, how much additional sales tax will I have to pay?

Solve the equation $11.59 x - 8.34 y = 11.51$ for $y$ .

The sales tax $T$ , in dollars, I have to pay when I buy D dollars worth of merchandise is giv- en by $T = 0.08 D$ . If I decide to buy $35 more in merchandise, how much additional sales tax will I have to pay?

The following table shows the running speed , in centimeters per second, of ants as a func- tion of the temperature $T$ in degrees Celsius. Use linear regression to model running speed as a function of Temperature.

Suppose $f$ is a linear function with $f ( 7 ) = 22.69$ and $f ( 11 ) = 33.37$ . Find an equation for $f$ .

The following table shows the depth D , in inches, of water in a pond after $d$ days of eva- poration. Find a linear model for depth as a function of days.

Suppose $f$ is a linear function with $f ( 6 ) = 20.98$ and $f ( 10 ) = 30.3$ . Find an equation for $f$ .