Sample Test For Unit

Test questions for objectives Unit: Linear functions

1. Determine whether a relation is a function. Which set of ordered pairs is not a function? a. {(1,5), (1,10)} b. {(2,4), (5,4)} c. {(4,6), (6, 9)} d. {(5,2), (10,19)} The set of ordered pairs {(-2,3),(2,-3),(4,2),(2,-4)} is a function. a. True b. False The ordered pair (1,7) is on the line defined by the equation 2x + y = 9. a. True b. False In a function, the first coordinate in each set of ordered pairs must be the same. a. True b. False

2. Describe the domain and range of a function. List the domain of the set {(9,-5), (4,5), (3, -2)}. List the range of the set {(9, -5), (4,5), (3, -2)}.

The domain of a set of ordered pairs consists of all the first coordinates of each set of ordered pairs. a. True b. False Fill in the missing number of each ordered pair so that it satisfies the equation 2x – y = 14. a. (8, _) b. (5, _) c. (_, 6)

3. Calculate the slope of a line by using the rise and run. Calculate slope given that the rise = 1 and the run = -5. Calculate slope given that the rise = -1 and the run = -7 Calculate slope given that the rise = 5 and the run = -3 Calculate slope given that the rise = 9 and the run = -5

4. Calculate the slope of a line from the ratio of the differences in x and y-coordinates. Find the slope of a line that contains the point (9, 6) and (1,4). Find the slope of a line that contains the point (2, 24) and (2,,9) Draw a graph of the line that contains the point (5,4) and has a slope of m=2/3. Draw a graph of the line that contains the point (-3,4) and has a slope of m=1/2.

5. Find the rate of change from a graph. The rate of change is equal to change in distance divided by the change in __________. The following graph shows an employees wages as a function of the number of hours that he works in a day. (Insert graph here). a. If the employee works 8 hours a day, what is his hourly rate of pay? b. If the employee works after 8 hours (overtime pay) what is his hourly

rate? The graph below show the monthly cost of renting videos. Find the rate of change, or cost per video. (insert graph)

6. Solve and graph direct-variation equations. If y varies directly as x and y=7 when x = 28, write an equation of direct variation. For the following values of x and y, y varies directly as x. find the missing value. y is 14 when x is 2. Find x when y is 21. y is 5 when x is 8. Find y when x is 28. Suppose that the hourly wage at a job is $8. Let x represent the number of hours, and let y represent the total amount earned. Write an equation of the direct variation and graph the equation.

An airplane ascends at a rate of 2,000 feet per per minute. Write an equation of direct variation, and graph the equation.

7. Define and explain the components of the slope-intercept form of a linear equation. The slope-intercept form allows you to write an equation for a line when you can only identify the slope and ____________. The equation for the slope-intercept form is ____________. How does changing the value of m affect the graph of y = mx + b? How does changing the value of b affect the graph of y = mx + b?

8. Use the slope-intercept form of a linear equation. Draw a graph of the equation y = 2x – 8. Given the two points (5, 65) and (3, 57), what is the equation using slope-intercept form? Is 3x – 4y = 7 a linear function? _________ In the equation 3x – 4y = 7 what is the y-intercept? ______.

9. Define and use the standard form of a linear equation. A linear equation in the form Ax + By = C is the standard form of a linear equation. a. True b. False

Write the equation y = -2x + 3 in standard form. Write the equation 3x = -7y - 17 in standard form. What is the standard form of a linear equation? a. Ax + By = C b. x = y + b c y = mx + b 10. Define and use the point-slope form of a linear equation. The point-slope form of an equation is y – y1 = m(x – x1). A. True B. False Write an equation in the point-slope form for a line that contains the points (3, 6) and (-5, 2) and the change the equation to point-slope form. Write the equation for the point-slope form of a linear equation. The slope of a line is 3 and a point on the line is (2, 6). Write the pointslope form of the linear function.