Graphing Linear Equations

Graphing Linear Equations

a) There are three methods to graph a linear equation. One way is to find the x and y intercepts. Another method is to create a table, and substitute numbers in the equation. The last method is the slope intercept form.

b) – To graph the equation 2x + y = 3, using the x and y intercept method, first find the x intercept. Do this by setting y to zero.

Therefore, 2x = 3 

  x = 1.5

(1.5, 0) is the x intercept.

To find the y intercept, set x as zero.

Therefore, y = 3

(0, 3) is the y intercept.

Plot these two points on the graph and draw a line joining the points.

 - To graph the equation using a table, first put it into function form.

2x + y = 3

y = 3 – 2x

Then create a table of x and y values, and choose several numbers to be the x values in the table.

X | Y

1 | 3 – 2(1) = 1 (1, 1)

2 | 3 – 2(2) = -1 (2, -1) 

3 | 3 – 2(3) = -3 (3, -3)

Plot these points and draw a line.

 - To graph a linear equation using the slope intercept form, change it into function form.

2x + y = 3

y = 3 – 2x

The number connected to the x value is the slope, and the isolated number is the y intercept. 

Therefore,

3 = y intercept.

-2 = slope. 

 1

Plot the y intercept and move down two and across one. The fraction of the slope represents rise

  run

Once two or more points are plotted, draw a line connecting the points.