Exam 8: The Slope of a Line

The slope of the line is and one point on a line is . Find the equation of the line and write the answer in slope-intercept form.

Let Evaluate

z varies jointly with x and the square of y . If z is 320 when x and y are 4, find z when x = 3 and y = 2.

Let and . Find . __________

Write the equation of the line with the slope m = 4 and y -intercept b = 6.

Line l contains the points (9, 4) and (-9, 3). Give the slope of any line perpendicular to l .

Find the slope of the line from the graph.

The slope of the line is m = 3 and one point on a line is (- 1, - 6). Find the equation of the line and write the answer in slope-intercept form.

Find the slope of the line through the pair of points (1, 6) and (5, 4). Then, plot the points, draw a line through them, and indicate the rise and run on the graph.

A musical tone's pitch varies inversely with its wavelength. If one tone has a pitch of 420 vibrations each second and a wavelength of 2.1 meters, find the wavelength of a tone that has a pitch of 690 vibrations each second. Please round your answer to the nearest hundredth.

A rectangle is 6 inches longer than it is wide. Let x = the width, P = the perimeter and A = the area of the rectangle. Write an equation that will give the perimeter P in terms of the width x of the rectangle.

Let and . Find the composition .

Given f = x ² - 8 x - 9 and g ( x ) = x - 4, find the following. ( f + g ) ( 0 )

Let Evaluate

Let and Evaluate

Determine if each of the following tables could represent ordered pairs from an equation of a line.

Straight-line depreciation is an accounting method used to help spread the cost of new equipment over a number of years. It takes into account both the cost when new and the salvage value, which is the value of the equipment at the time it gets replaced. The function where V is value and t is time in years, can be used to find the value of a large copy machine during the first 4 years of use. What is the value of the copier after 1 years and 3 months?

y varies inversely with the square of x . If y = 50 when x = 5, find y when x is 2.

y varies inversely with the square of x . If y = 45 when x = 3, find y when x is 5.

The training heart rate , in beats per minute, is the resting heart rate plus 60% of the difference between the maximum heart rate and resting heart rate. Your maximum heart rate is found by subtracting your age in years from 220. Find the training heart rate function, , for a person with a resting heart rate of 72 beats per minute, then find the following to the nearest whole number. a. Find the maximum heart rate function, , for a person years of age. b. What is the maximum heart rate for a 18-year-old person? __________ beats per minute c. What is the training heart rate for a 18-year-old person with a resting heart rate of 72 beats per minute? __________ beats per minute d. What is the training heart rate for a 28-year-old person with a resting heart rate of 72 beats per minute? __________ beats per minute e. What is the training heart rate for a 38-year-old person with a resting heart rate of 72 beats per minute? __________ beats per minute