1. How to make a quick and easy graph of a linear equation!
Interceptions!
How to make a quick and easy graph of a linear equation!

2. What is an intercept?
Think football… what happens when the ball is intercepted?
In math, it works the same way. The y intercept is the point where the line “catches” the y axis! The x intercept is where the line “catches” the x-axis!

3. Name those intercepts

4. How do I find the intercepts without graphing?
What did you notice about the ordered pair of each intercept?
To find the x intercept substitute 0 for y in the linear equation
To find the y intercept substitute 0 for x in the linear equation

5. Try a few! Find the x and y intercepts of these linear equations!
2 x + 3 y = 6
3 x – 6 y = - 18
y = ½ x - 7

6. How does this help in graphing?
By finding the x and y intercepts for a linear equation, there is no need to find three solutions using the function/ input-output chart!
Just find the intercepts, connect the points and you are good to go!

7. So try it and see!
Quickly graph 4x – 2y = 8 using the intercepts!

8. You are trying to raise money for your football team
You are trying to raise money for your football team. You know you can sell 200 adult tickets and 100 student tickets for the game. You MUST raise $1500!!! What are all the possible solutions to this problem?

9. Summary y- intercept x-intercept
What does it mean to intercept a pass in football?
The other team catches the ball (picks it off).
Think of the path of a football as a line.
What happens to the path when the ball is intercepted? The path stops.
Where could this football be intercepted? -2 on the x-axis or 1 on the y-axis. y 4 3 2 1
y-intercept (0,1)
x-intercept (-2,0) -1 -2 -3 x y-
intercept
x-intercept
The x-intercept of a graphed line is the point
on the x-axis that the line passes through.
The y-intercept of a graphed line is the point
on the y-axis that the line passes through.
an sbl original ‘06