graphing: Will graph of y = 2x + 7 pass below the origin?

[srgdean]

True or False: The graph of y=2x+7 will pass below the origin.

Why is this false?

[tkhunny]

y = mx + b

y-intercept is y = 7.

Generally, +7 is considered "above" the origin.

[srgdean]

What if x=-20 then y would equal -33?

[tkhunny]

"pass below" implies x = 0.

On a highway, are you "below" a bridge when you are 20 miles from the bridge?

[srgdean]

So are you saying it would have to be on the y axis?

[stapel]

So are you saying it would have to be on the y axis?

Try graphing the line. Look at the picture. Compare the line with the location of the origin. What do you see?

Eliz.

[tkhunny]

So are you saying it would have to be on the y axis?

That is what "pass below" means to me.

[srgdean]

Thanks, I see now.