X and Y Intercepts
The y intercept is the point at which the graph of an equation crosses the
y axis.
y
(0,3)
x
y = 2x + 3
The y intercept is the point at which the graph of an equation crosses the
y axis.
y
(0,3)
x
Notice that the x value is zero.
y = 2x + 3
The x intercept is the point at which the graph of an equation crosses the
x axis.
y
(-3/2 ,0)
x
y = 2x + 3
The x intercept is the point at which the graph of an equation crosses the
x axis.
y
(-3/2 ,0)
xNotice that the y value is zero.
y = 2x + 3
Example #1 Find the y and x intercepts. Then graph the line.
y = 2x + 6
Example #1 Find the y and x intercepts. Then graph the line.
y = 2x + 6
y intercepty = 2(0) + 6
y = 6(0,6)
y = 2x + 6
y intercepty = 2(0) + 6
y = 6(0,6)
x intercept0 = 2x + 6
x = -3(-3,0)
Example #1 Find the y and x intercepts. Then graph the line.
Example #1 Find the y and x intercepts. Then graph the line.
y = 2x + 6
(0,6)
(-3,0)
y
x
Example #1 Find the y and x intercepts. Then graph the line.
y = 2x + 6
(0,6)
(-3,0)
y
x
Example #2 Find the y and x intercepts. Then graph the line.
y = 3x + 12
Example #2 Find the y and x intercepts. Then graph the line.
y = 3x + 12
y intercepty = 3(0) + 12
y = 12(0,12)
Example #2 Find the y and x intercepts. Then graph the line.
y = 3x + 12
y intercepty = 3(0) + 12
y = 12(0,12)
x intercept0 = 3x + 12
x = -4(-4,0)
Example #2 Find the y and x intercepts. Then graph the line.
y = 3x + 12
(0,12)
(-4,0)
y
x
Example #2 Find the y and x intercepts. Then graph the line.
y = 3x + 12
(0,12)
(-4,0)
y
x
Practice Time
For each function, find the x and y intercepts. Then graph the line.
1) y = ½ x + 4
1) y = ½ x + 4
y intercepty = ½ (0) + 4
y = 4(0,4)
x intercept0 = ½ x + 4
x = -8(-8,0)
1) y = ½ x + 4
(0,4)
(-8,0)
y
x
2) y = -2 x + 8
2) y = -2 x + 8
y intercepty = -2 (0) + 8
y = 8(0,8)
x intercept0 = -2 x + 8
x = 4(4,0)
2) y = -2 x + 8
(0,8)
(4,0)
y
x
3) y = -3x - 4
3) y = -3x - 4
y intercepty = -3 (0) - 4
y = -4(0,-4)
x intercept0 = -3 x - 4
x = -4/3
(-4/3,0)
3) y = -3x - 4
(0,-4)
(-4/3,0)
y
x
4) y = 8x - 2
4) y = 8x - 2
y intercepty = 8 (0) - 2
y = -2(0,-2)
x intercept0 = 8 x - 2
x = 1/4
(1/4,0)
4) y = 8x - 2
(0,-2)
(1/4,0)
y
x
5) 2x + 3y = 6
5) 2x + 3y = 6
y intercept2(0) + 3y = 6
y = 2(0,2)
x intercept2x + 3(0) = 6
x = 3(3,0)
5) 2x + 3y = 6
(0,2)
(3,0)
y
x
6) 5x + 2y = 10
6) 5x + 2y = 10
y intercept5(0) + 2y = 10
y = 5(0,5)
x intercept5x + 2(0) = 10
x = 2(2,0)
6) 5x + 2y = 10
(0,5)
(2,0)
y
x
7) -3x + 5y = 9
7) -3x + 5y = 9
y intercept-3(0) + 5y = 9
y = 9/5
(0,9/5)
x intercept-3x + 5(0) = 9
x = -3(-3,0)
7) -3x + 5y = 9
(0,9/5)(-3,0)
y
x
8) -2x - 3y = 10
8) -2x - 3y = 10
y intercept-2(0) - 3y = 10
y = -10/3
(0,-10/3)
x intercept-2x - 3(0) = 10
x = -5(-5,0)
8) -2x - 3y = 10
(0,-10/3)
(-5,0)
y