posted by Jake .
Graph y=2x+1, then choose 3 points above the line. Give the coordinates of each point and tell wether it is greater than, less than or equal to
2x + 1 at each point.
for any point that you choose above the line, the y-coordinate of that point would be greater than 2x+1
Doesn't the line go on forever, so how could you choose 3 points above it?
did you draw the line.
for any line, unless it is vertical, you can be either above or below the line.
e.g. for your y = 2x + 1
consider (6,5), below above the line.
substitute the value x = 6
then y = 2(6)+1 = 13, but the y for your point was 5
since 5 < 13, the point (6,5) is below the line.
if x=3 in the equation y = 6+1 = 7
since 15 > 7, the point (3,15) is above the line.
Draw any non-vertical line on a piece of paper. Isn't there a region above that line and a region below that line no matter you imagine that line to go ??