How do you graph the line #x+2y=4#?

2 Answers
Apr 8, 2017

Answer:

#x + 2y# isn't a line but a 3D function.

Explanation:

As you have two different variables (x and y) you aren't looking at a linear function but at a 3d function instead. Make sure you have the correct heading (or perhaps its mistaken in your book?)!

However, this is what it'd look like:

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If the heading was mistaken or you copied it down incorrectly, and you have a new linear graph you don't know how to plot, please let me know and I'll try to help you out :)

Apr 8, 2017

Answer:

Identify the #x# and #y# intercepts, then draw the line through them.

Explanation:

Given:

#x+2y = 4#

Note that this equation is linear, since all of the terms in #x# and #y# are of degree at most #1#.

We can find the line's #x# intercept by setting #y=0#, or equivalently covering up the #y# term to find:

#x = 4#

So the intersection with the #x# axis (which has equation #y=0#) is the point #(4, 0)#.

Similarly, we can find the line's #y# intercept by setting #x=0#, or equivalently covering up the #x# term to find:

#2y=4#

and hence:

#y = 2#

So the intersection with the #y# axis (which has equation #x=0#) is the point #(0, 2)#.

Now we can draw our line through those two points:

graph{(x+2y-4)((x-4)^2+y^2-0.02)(x^2+(y-2)^2-0.02) = 0 [-7.58, 12.42, -4.04, 5.96]}