1. Graphing Linear Equations
In Standard Form
Ax + By = C

2. of the equation to graph the line.
Linear equations have two variables and when we plot all the (x,y) pairs that make the equation true we get a line.
We will use
The Standard
Form
of the equation to graph the line.

3. Ax + By = C The formula for Standard Form is:
We can find 3 things just by looking at the formula:
To find where the line crosses each axis,
let the other value be zero.
If y is zero, we have Ax = C
is the x-intercept.
If x is zero, we have By = C
is the y-intercept.
− — is the slope. A B
Using the x-intercept and/or y-intercept as a starting point, you can use the slope to graph more points on the line of the equation.

4. 2x – y = -1 x + y = -4 3x – 2y = 4 These equations are all in
Standard Form:
2x – y = -1
x + y = -4
3x – 2y = 4
Notice that these equations are all in the form Ax + By = C.

5. 2x – y = -1 Find the x-intercept: -1 ÷ 2 = -1/2
2) Find the y-intercept:
-1 ÷ -1 = 1
3) Plot the y-intercept.
right 1
up 2
right 1
up 2
4) Find the slope: -A/B
− 2/-1 = 2
5) Plot more points using the slope.

6. x + y = -4 Find the x-intercept: -4 ÷ 1 = -4 2) Find the y-intercept:
3) Plot the x and y-intercepts.
left 1
4) Find the slope: -a/b
− 1/1 = -1
5) Plot more points using the slope.
up 1
down 1
right 1

7. A graph with only one letter (x or y) only crosses that axis at that point.
ONLY crosses the x-axis…
at -3
y = 5
ONLY crosses the y-axis…
at 5

8. The formula for Standard Form is:
SUMMARY
The formula for Standard Form is:
Ax + By = C
If y=0, C ÷ A gives the
x-intercept
If x=0, C ÷ B gives the
y-intercept
− — is the
slope A B
Using the x-intercept and/or y-intercept as a starting point, you can use the slope to graph the line of the equation.