Math Checkup Unit 1 Lesson 3

Checkup: Linear Functions

Answer the following questions using what you've learned from this lesson. Write your responses in the space provided, and turn the assignment in to your instructor.

1. What is the slope of the line in the graph below? Show your work.

Answer:

To find out the slope, you must first take two separate points on the graph, such as (-5,-1) and (0,1). Then, it’s a simple matter to use the equation [pic] to find the slope:

[pic]= [pic]

2. What is the slope of the line represented by the table of values below? How do you know?
|x |y |
|-2 |3 |
|-1 |4.5 |
|0 |6 |
|1 |7.5 |
|2 |9 |

Answer:
By taking two different (x,y) values from the table and using the [pic] formula, we can easily find the slope. For example, let’s use (-2,3) and (0,6):
[pic]= [pic]
3. Which of the following graphs could be the graph of y = - 4x - 5? Circle the letter of your answer(s) and explain your choice(s).

a.

b.

c.

d.

4. Write the equation of the line that passes through the points (3,7) and (-1,2) in:

The slope is [pic]=[pic]=[pic]

a. Point-slope form

y-2=[pic](x+1)

b. Slope-intercept form

y=[pic]x+[pic]

5. What is the slope of a line that is perpendicular to [pic]? Show your work.
Answer: A line perpendicular to y=[pic]x would have a slope that’s the reciprocal of the slope to y=[pic]x. So the answer is [pic].

6. Write the equation of a line passing through (0,6) and parallel to the line [pic].
Answer:

y=[pic]x+6

7. Which of the following tables of values could have been generated by a linear function? How do you know?

a.
|x |y |
|-2 |