1. X and Y Intercepts

2. X-intercept:
the x-intercept of a line is where it crosses the x axis
So, set y=0 in the equation and solve for x.
x-intercept as an ordered pair is always x value and y=0 (#,0)

3. Y-intercept:
the y-intercept of a line is where it crosses the y axis
So, set x=0 in the equation and solve for y.
y-intercept as an ordered pair is always y value and x=0 (0,#)

4. DO NOT PUT THE X VALUE AND Y VALUE TOGETHER AS ONE ORDERED PAIR!!!!
They are 2 different points
(#,0) and (0,#)

5. A Quick Way to Graph an Equation:
Find where the line crosses the x and y axis
Plot the intercepts
Connect the two points.

6. Plug in x=0 and solve for y Plug in y=0 and solve for x
Find the x and y-intercepts and graph 2x+3y=12
Find y-intercept:
Plug in x=0 and solve for y
Find x-intercept:
Plug in y=0 and solve for x
2x+3y=12
2x+3y=12
2(0)+3y=12
2x+3(0)=12
3y=12
2x=12
y=4
x=6
(6, 0)
(0, 4)

7. To Graph: (0, 4) (6, 0) Plot the x and y intercepts Connect the dots!5 4 3
(0, 4)
(6, 0) 2 1

8. Plug in x=0 and solve for y Plug in y=0 and solve for x
Find the x & y intercepts and graph -4x+6y=18
Find y-intercept:
Plug in x=0 and solve for y
Find x-intercept:
Plug in y=0 and solve for x
-4x+6y=18
-4x+6y=18
-4(0)+6y=18
-4x+6(0)=18
6y=18
-4x=18
y=3
x=-4 ½
(0, 3)
(-4 ½ , 0)

9. Graph 6
(0, 3)
(-4 ½ , 0) 5 4 3 2 1

10. Find y-intercept: it’s the b in y=mx+b Plug in y=0 and solve for x
Find the x & y intercepts and graph y=-3/2x + 9
Find y-intercept: it’s the b in y=mx+b
Find x-intercept:
Plug in y=0 and solve for x
y=-3/2x+9
y=-3/2x+9
0=-3/2x+9
b=9
-9=-3/2x
6=x
(0, 9)
(6 , 0)

11. Graph 9
(0, 9)
(6 , 0) 8 7 6 5 4 3 2 1
*double check graph in slope-intercept form – start at 9?, slope down 3 over 2?