Using “T” Tables & Graphing Intercepts x-intercept y-intercept
Using a “T” Table The minimum number of points needed to graph a line is 2. However, 3 or greater is more accurate. Graph the equation 3x + y = 6 by making a “T” Table and graphing the line.
3x + y = 6 y x 1 3
3x + y = 6 y x 1 3 2
3x + y = 6 y x 1 3 2 6
Now DRAW the Line Y (1,3) X (2,0) (0,6)
Definition - Intercepts The x-intercept of a straight line is the x-coordinate of the point where the graph crosses the x-axis. The y-intercept of a straight line is the y-coordinate of the point where the graph crosses the y-axis. y-intercept x-intercept
Intercepts Finding the x-intercept & y-intercept is like filling in this t-table when x = 0 and you solve for y, and when y = 0 solving for x. y x ? ?
Finding the intercepts 3x + y = 6 To find the x-intercept, let y = 0 3x + (0) = 6 3x = 6 x = 2
Finding the intercepts 3x + y = 6 To find the y-intercept, let x = 0 3(0) + y = 6 y = 6
The graph of 3x + y = 6 Y y-intercept = 6 x-intercept = 2 X
Find the intercepts and graph 3x + 4y = 12
Finding the x-intercept 3x + 4y = 12 3x + 4(0) = 12 3x + 0 = 12 3x = 12 x = 4
Finding the y-intercept 3x + 4y = 12 3(0) + 4y = 12 0 + 4y = 12 4y = 12 y = 3
The graph of 3x + 4y = 12 Y y-intercept = 3 x-intercept = 4 X
Find the intercepts and graph y = 4x - 4 You try this one.
Finding the x-intercept y = 4x - 4 0 = 4x - 4 0 + 4 = 4x -4 + 4 4 = 4x 1 = x
Finding the y-intercept y = 4x - 4 y = 4(0) - 4 y = -4
The graph of y = 4x - 4 Y x-intercept = 1 X y-intercept = -4
Name the x-intercept and the y-intercept of the equation graphed below. The x-intercept occurs when y = 0 ( 2 , 0) The y-intercept occurs when x = 0 (0, -3)