Chapter 4

Question 1

How do you properly graph linear equations?

Answer 1

1) Make a table of values
2) Plot ordered pairs
3) Draw a line through the points
4) Make sure line is accurate (corner to corner, arrows on the ends)
5) Write equation on graph

Question 2

The graph of x=a is a horizontal line passing through _______.

Answer 2

the y axis
(0,b)

Question 3

The graph of x=a is a vertical line passing through ______.

Answer 3

The x axis
(a,0)

Question 4

Make a table for the equation y = 1/2x - 1

Answer 4

x y
0 -1
2 0
4 1

Plug the numbers in the x column into the equation

Question 5

Find the slope of the line through the points (3,7) and (5,19)

Answer 5

m= 19-7/5-3 = m= 12/2

m=6

Question 6

Is a zero line horizontal or vertical?

Answer 6

Horizontal

Question 7

Is a undefined line horizontal or vertical?

Answer 7

Vertical

Question 8

Is the top of a positive line in quadrant I or II?

Answer 8

Quadrant I

Question 9

Is the top of a negative line in quadrant I or II?

Answer 9

Quadrant II

Question 10

x y
1 2
3 10
5 18
7 26

Find the slope.

Answer 10

m = 4

Question 11

(r,3) (5,9)

m = 2

Find the value of r

Answer 11

r = 2

Question 12

Non Vertical parallel lines have the ______ _______.

Answer 12

Same slope.

Question 13

The graph of _______ is a line with a slope of m that passes through the ______.

Answer 13

y=mx+b

origin

Question 14

On a graph, direct variation must be a ________ ____ and go through the _____.

Answer 14

Straight line
Origin

Question 15

In y = mx + b, b equals?

Answer 15

The initial value
y intercept

Question 16

In y = mx + b, m equals?

Answer 16

The rate of change, or slope

Question 17

Suppose y directly varies with x.
If y is 20 when x = 4, find y when x = 3

Answer 17

y = 15

Question 18

Suppose y varies with x.
If y is 2 when x=8, find x when y equals 9.

Answer 18

x = 36

Question 19

y = -7x + 9
Find the slope and y intercept.

Answer 19

Slope: -7/1
Y intercept: 9

Question 20

y = x - 12
Find the slope and y intercept.

Answer 20

Slope: 1/1
Y intercept: -12

Question 21

y + 8 = -3x
Find the slope and y intercept.

Answer 21

Slope: -3/1
Y intercept: -8

Question 22

2y + 10 = 4x
Find the slope and y intercept.

Answer 22

Slope: 2/1
Y intercept: -5

Question 23

The height (y) of a moveable bridge after rising for x seconds is represented by the equation y = 3x+ 16. Interpret the y intercept and slope.

How many seconds does it take for the bridge to reach a height of 76 feet?

Answer 23

x = 20

The bridge has a height of 16 feet and rises 3 feet per second.

It would take 20 seconds for the bridge to reach a height of 76 feet.

Question 24

The cost (y) in dollars for making x friendship bracelets is represented by the equation y = 0.5x + 2. Interpret the y intercept and slope.

Answer 24

The bracelets cost 2 dollars plus 50 cents per bracelet

Question 25

The number of perfume bottles in storage after x months is represented by the equation y = -20 + 460. Interpret the y intercept and slope. In how many months will there be no perfume bottles left in storage.

Answer 25

There were 460 bottles, and 20 bottles get taken out per month. It will take 23 months for there to be no more bottles in storage.

Question 26

5x + y = -5 Find the X and Y intercepts.

Answer 26

x intercept = -1 y intercept = -5

Question 27

2x + 9y = 18 Find the X and Y intercepts.

Answer 27

x intercept = 9 y intercept = 2

Question 28

1.5x + 0.6y = 6 Find the X and Y intercepts.

Answer 28

x intercept = 4 y intercept = 10

Question 29

1.2x + 0.8y = 12 Find the X and Y intercepts.

Answer 29

x intercept = 10 y intercept = 15

Question 30

Students tickets cost 9 dollars and general tickets cost 15 dollars. On one day they collected 4500 dollars. If X represents student tickets and y represents general tickets, find the x and y intercepts. Interpret the x and y intercepts.

Answer 30

9x + 15y = 4500 x intercept = 500 y intercept = 300 You could buy 500 student tickets and 0 general tickets. You could buy 300 general tickets and 0 student tickets.

Question 31

Is 5x + y = -5 in slope intercept form?

Answer 31

No, standard form