Question 49393: Graph:
y "is less than or equal to sign" 2x-2
Thanks!
Can you show me how one tutor got the points (0,-2) and (1,0) through the problem because that's the one part I really don't understand.
Thanks again!
Answer by Born2TeachMath(20)   (Show Source):
You can put this solution on YOUR website! Graph of y <= 2x - 2.
The important part is to graph the line first.
Your tutor chose to use the intercept method, which means to find the two points where the line crosses the x- and y-axes. To find the intercepts, a point is an intercept when the opposite point coordinate is zero. (Think - a point on the x-axis has a y-value of 0, and a point on the y-axis has an x-coordinate of 0!)
Therefore: x-intercept (y = 0)
0 = 2x - 2
2 = 2x
1 = x,
so the first point is (1, 0)
y-intercept: (x = 0)
y = 2(0) - 2
y = 0 - 2
y = -2
so the second point is (0, -2)
That is how the tutor found the two points to plot.
I wouldn't do it that way. WIth the equation y = 2x - 2, this is in slope-intercept form. If you know about this, the 2 from the 2x is the slope, and the -2 is the y-intercept.
So to plot this line, start by plotting the y-intercept of -2, or a point on the y-axis 2 units below the origin.
Then, FROM THERE (not the origin), we move the slope of 2/1 (change it into a fraction), so we move up two units and over one unit, which gives us the point (1, 0). Draw the line between these two, and then shade, etc...
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