Exam 2: Graphs, Lines, and Inequalities

Solve the problem using your calculator. -A study was conducted to compare the average time spent in the lab each week versus course grade for computer students. The results are recorded in the table below. Use linear regression to find a linear function that predicts a student's course grade as a function of the number of hours spent in lab.

Solve the problem. -A coin is tossed upward from a balcony $252 \mathrm{ft}$ high with an initial velocity of $16 \mathrm{ft} / \mathrm{sec}$ . During what interval of time will the coin be at a height of at least $60 \mathrm{ft}$ ? $\left(\mathrm{h}=-16 \mathrm{t}^{2}+\mathrm{v}_{0} \mathrm{t}+\mathrm{h}_{0}\right.$ . $)$

Write an equation in standard form for a line passing through the pair of points. - $(-7,-2)$ and $(0,-5)$

Solve the inequality. - $\frac{x^{2}-12 x+27}{x-5}>0$

Use a graphing calculator to find the graph of the equation. - $y=x^{4}+x^{3}-5 x^{2}-4 x+4$

Solve the inequality and graph the solution. - $x^{2}+4 x \leq-3$

Write an equation in slope-intercept form of a line satisfying the given conditions. - $\mathrm{m}=\frac{5}{2}$ ; $\mathrm{b}=-2$

Write an equation in slope-intercept form of a line satisfying the given conditions. - $\mathrm{m}=-\frac{3}{7} ; \mathrm{b}=\frac{20}{7}$

Find an equation of the the line satisfying the given conditions. -Through (8,-2); parallel to $-4 x+6 y=-20$

Use technology to compute $r$ , the correlation coefficient. -The following are the temperatures on randomly chosen days and the amount a certain kind of plant grew (in millimeters):

Solve the problem. -The paired data below consist of the test scores of 6 randomly selected students and the number of hours they studied for the test. By using linear regression, the following equation is obtained: $y=67.3+1.07 x$ where $x$ is number of hours studied and $y$ is score on the test. Use this equation to predict the score on the test of a student who studies 14 hours.

Solve the inequality. - $\frac{2 x}{6-x}>x$

Determine whether the given ordered pair is a solution of the given equation. - $\frac{x^{2}}{6}+\frac{y^{2}}{3}=1 ;(1,-1)$

Find an equation of the the line satisfying the given conditions. -Th rough the origin with slope 9

Find the x-intercepts and y-intercepts of the graph of the equation. - $x+y=0$

Solve the inequality and graph the solution. - $5|x+2| \geq 4$

Solve the problem. -The cost, $c$ , in dollars of car rental is $5+\frac{1}{4} \mathrm{~m}$ , where $\mathrm{m}$ is the number of miles driven. Graph the equation and use the graph to estimate the cost of car rental if the number of miles driven is 35 .

Find an equation of the line with slope m that passes through the given point. Put the answer in slope-intercept form. - $(-3,-9), m=0$

Solve the problem. -The paired data below consist of the temperatures on randomly chosen days and the amount a certain kind of plant grew (in millimeters). By using linear regression, the following equation is obtained: $\mathrm{y}=14.6+0.211 \mathrm{x}$ where $\mathrm{x}$ is temperature and $\mathrm{y}$ is growth in millimeters. Use this equation to predict the growth of a plant if the temperature is 79 .

Solve the problem. -The information in the chart gives the salary of a person for the stated years. Model the data with a linear equation using the points $(1,24,300)$ and $(3,26,600)$ .