Exam 1: Linear Functions and Change

Find the $x$ -coordinate of the point $\mathrm{P}$ shown in the following figure. Round to 3 decimal places.

Suppose that f(x) is linear and that $f(4)=1$ and $f(0)=-7$ . If $f(x)=b+m x$ , then $b=―――$ and $m=―――$

You need to purchase a new computer printer. The cost of printer $A$ is $\$ 80$ , and its ink cartridges are $\$ 29$ each. The cost of printer $B$ is $\$ 125$ , and its ink cartridges are $\$ 15$ each. You estimate that you will need new ink cartridges about once a month. Find equations for the total cost of each printer after $t$ months and use them to determine when you would have invested about the same amount of money in each. Round to the nearest tenth of a month.

What is the slope of the line $y=\frac{5}{6} x+1$ ?

A wildlife ranger finds that there is a linear relationship between the number of bushels of corn distributed in a month and the number of deer at the park. If the ranger distributes no bushels of corn, there are 49 deer at the park. For each additional bushel of corn distributed, 7 more deer come to the park. How many bushels of corn must be distributed in order to have 77 deer at the park?

Match the graph to the linear inequality it represents.

Determine the slope of a line parallel to $y=\frac{8}{5} x-8$

Does the following graph give $y$ as a function of $x$ ?

Determine the point of intersection of the linear functions y=2 x+4 y=3 x+7

The population of a pack of rats can be represented by the formula $P(t)=2+1.3 t$ where $P(t)=2+1.3 t$ represents the population in hundreds, and $t$ represents the time, in months, since January 2010. Which of the following is correct regarding the slope.

Mark all of the following functions that are neither increasing nor decreasing.

Consider the information in the following table. Could $t$ be a function of $s$ ?

Many economists believe that a country's inflation rate will rise if its unemployment rate falls. The following figure show the relationship between the inflation rate, $I$ , and the unemployment rate, $u$ , in four different countries. In which of the four countries does the relationship between the inflation rate and the unemployment rate seem opposite of what is normally expected?

If you were to draw a graph representing the total amount of concrete, $A$ , used to pour $x$ square feet of sidewalk, which axis would $x$ be on?

Use the following table to find $p(20)$ . If there is more than one answer, enter the smallest first and separate them by semicolons.

Express this relationship in function notation (that is, $y$ is a function of $x$ is written $y=$ $f(x)$ ). Calories burned, $c$ , is a function of activity, $a$ .

A salesman earns $W(n)=500+175 n$ , where $n$ is the number of products sold, and $W(n)$ is the weekly wage in dollars. What does the number 500 represent? (Mark all that apply)

A wildlife ranger finds that there is a linear relationship between the number of bushels of corn distributed in a month and the number of deer at the park. If the ranger distributes no bushels of corn, there are 49 deer at the park. For each additional bushel of corn distributed, 8 more deer come to the park. a) If $d$ is the number of deer at the park and $b$ is the number of bushels of corn fed in a month, find a formula for $d$ in terms of $b$ . b) How many deer are at the park if the ranger feeds 3 bushels of corn? c) How many bushels of corn must be distributed in order to have 81 deer at the park?

Could the following table represent a linear function?

Several years ago, the wild rabbits of Australia were seriously threatened by a virus that was accidentally released into their population. Suppose that the following table gives the number $r$ of rabbits (in millions) remaining $t$ months after the release of the virus. t (months) 2 4 6 8 10 12 14 16 18 20 r (millions) 1940 1842 1649 1328 1140 898 765 502 296 104 Find the linear regression line for this data. Round to 3 decimal places.