Equations Tables and

Graphs

These are all connected to each other. They all show the same information but in different forms

Equation y = 6x + 8Table x y

Ordered pair (x,y)

GraphSlope

x -3 -2 -1 0 1 2 3

y              

Straight Lines

When given an equation and told to plot a graph, first find coordinates of points on the line, this is done by completing a table.

By substituting the given values for x calculate the y value for the following equation:

y = x + 2

-1 0 1 2 3 4 5

This generates coordinates to plot on a graph

(-3,-1)(-2,0)(-1, 1)

(0, 2)

(0, 2)(1, 3)

(2, 4)(3, 5)

Straight Lines(-3,-1)(-2,0)(-1, 1)

(0, 2)

(0, 2)(1, 3)

(2, 4)(3, 5)

0 1 2 3 4 5 6 7 8 9 10-9 -8 -7 -6 -5 -4 -3 -2 -1-10 x

y

1

2

3

4

5

6

7

8

9

10

-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

Plotting these points

xx

xx

xx

xx

We find a straight line

Straight Lines

Copy and complete this table for the following equation and plot thestraight line

y = 3x - 1

0 1 2 3 4 5 6 7 8 9 10-9 -8 -7 -6 -5 -4 -3 -2 -1-10 x

y

1

2

3

4

5

6

7

8

9

10

-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

x -3 -1 0 1 3y -10 -4 -1 2 8

x

x

x

x

x

Straight Lines

0 1 2 3 4 5 6 7 8 9 10-9 -8 -7 -6 -5 -4 -3 -2 -1-10 x

y

1

2

3

4

5

6

7

8

9

10

-1

-2

-3

-4

-5

-6

-7

-8

-9

-10

Complete the table for the equation y = x

x -3 -1 0 1 3y

x -3 -1 0 1 3y

x -3 -1 0 1 3y

x -3 -1 0 1 3y

Complete the table for the equation y = x - 2

Complete the table for the equation y = x + 3

Complete the table for the equation y = x +1

Plot the coordinatesWhen the table is completed

Worksheet 1

What do I do if I don’t have the points given to me???

x

y              

y = 2x + 2

Graphing

Step 1: ~ Five Point Method ~

Choose 5 values for x

GraphingStep 2:

Find solutions using tabley = x + 3Y | X 0 1 2

Graphing

Step 3:

Graph the points from the table(0,3) (1,4) (2,5)

Graphing

Step 4:

Draw a line to connect them

Linear Equations:Equation of a straight line

Standard form is

AX + BY = C

Slope-Intercept

y = mx + bm = slope

b = y-intercept

Slope

Describes the steepness of a line or rate of

change

Y-intercept

Where the line crosses the

y-axis

Y-intercept

The y-intercept has an x-coordinate of

ZERO

Y-intercept

To find the y-intercept, plug in ZERO for x and

solve

X-intercept

Where the line crosses the

x-axis

X-intercept

The x-intercept has a y coordinate of

ZERO

X-intercept

To find the x-intercept, plug in ZERO for y and

solve

Try These

• Graph using a table (5 point method)

1) y = x + 3

2) y = x - 4

X Y

Equation:

A phone company charges $17.50 per month and 12 c for each additional minute . Write a linear equation for the charge in terms of the number of minutes.

Let C = charge in dollars

Let m = # of minutes

C = 17.50 + 0.12 m

ChangeStartValue

Platter Weight Price

1 lb. $2.10

2 lb. $3.60

3 lb. $5.10

4 lb. $6.60

5 lb. $8.10

This chart shows the price of sliced fruit platters. 1) How much would a

6 lb. platter cost?

1.50

1.50

1.50

1.50 $8.10 + 1.50 = $ 9.60

2) Write an equation forthe cost of a platter thatweighs w lbs.

Let p = price of platter

p = 1.50 w + 0.603) How much would a 10 lb.platter cost?

p = 1.50 w + 0.60p = 1.50 ( 10 ) + 0.60p = 15.00 + 0.60 = $15.60

Change StartValue

Y = 0.75X + 3You are visiting Baltimore, MD, and a taxi

company charges the flat fee of $3.00 for using the taxi and an additional &0.75 per mile. Write an equation that you could use to find the cost of a taxi ride in Baltimore, MD. Let X represent the number of miles and Y represent the total cost.

Kim and Cyndi are starting a business tutoring students in math. They rent an office for $100 per week and charge $40 per hour per student. If they have 15 students each for one hour per week how much profit do they make together in a week? Write and equation.

Suppose that the water level of a river is 34 feet and that it is receding at a rate of 0.5 foot per day. Write an equation for the water level, L, after d days. In how many days will the water level be 26 feet?