Exam 1: Straight Lines and Linear Functions

Sketch a set of coordinate axes and plot the given point. (1.5, -1.5)

Sketch the straight line defined by the linear equation by finding the x- and y- intercepts. ​ ​

The quantity demanded for a certain brand of portable CD players is 200 units when the unit price is set at $90. The quantity demanded is 1,200 units when the unit price is $40. Find the demand equation.

Find the slope of the line that passes through the given pair of points. (2, 4) and (8, 8)

Match the statement with one of the graphs. The slope of the line is negative, and its x-intercept is negative.

Determine whether the lines through the given pairs of points are parallel. Answer yes or no.

Sketch a set of coordinate axes and plot the given point.

The annual sales of Crimson Drug Store are expected to be given by million dollars t yr from now, whereas the annual sales of Cambridge Drug Store are expected to be given by million dollars t yr from now. When will Cambridge's annual sales first surpass Crimson's annual sales?

Find an equation of the vertical line that passes through .

Metro Department Store's annual sales (in millions of dollars) during 5 years were Plot the annual sales (y) versus the year (x) and draw a straight line L through the points corresponding to the first and fifth years and derive an equation of the line L.

The Social Security (FICA) wage base (in thousands of dollars) from 1996 to 2001 is given in the accompanying table: Find an equation of the least-squares line for these data. (Let x = 1 represent the year 1996.) Please round the coefficients in your equation to three decimal places. Use the result to estimate the FICA wage base in the year 2005.

Find the constants m and b in the linear function f(x) = mx + b so that f(2) = 6 and the straight line represented by f has slope - 1.

Find the equation of the least-squares line for the given data. Draw a scatter diagram for the given data and graph the least-squares line. Please round the coefficients in your equation to two decimal places.

Find the equation of the least-squares line for the given data. Draw a scatter diagram for the given data and graph the least-squares line.

With computer security always a hot-button issue, demand is growing for technology that authenticates and authorizes computer users. The following table gives the authentication software sales (in billions of dollars), including projections, from 1999 through 2004. (Here, x = 0 represents 1999.) Find an equation of the least-squares line for these data. Please round the coefficients in your equation to three decimal places. Use the result to estimate the sales for 2008, assuming the projection is accurate.

Find the distance between the given points. (- 1, 3) and (4, 15)

Find an equation of the circle that satisfies the given conditions. Radius 7 and center (5, - 4)

Sketch a set of coordinate axes and plot the given point.

Determine whether the statement is true or false. If it is true, explain why it is true. If it is false, give an example to show why it is false. The point (1, k) lies on the line with equation 5x + 4y = 20 if and only if .

Delivery Charges. A furniture store offers free setup and delivery services to all points within a 25-mi radius of its warehouse distribution center. If you live 21 mi east and 12 mi south of the warehouse, will you incur a delivery charge? Justify your answer.