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2018-09-10 00:20:35 -0600 commented answer Plotting systems of linear equations with 3 variables

Hello, You are correct. In my mind, I was looking for 3 lines, but mathematically those equations produce planes. Maybe I was trying to relate to 2 variable linear equations Please excuse my ignorance. Thank you, Steve.

2018-09-06 23:13:37 -0600 commented answer Plotting systems of linear equations with 3 variables

Thank you for your patience and help.

The goal is to create and image like the one at this link ( 3d Image so I can show a classroom of middle school and/or high school students what the solution to a system of linear equations that has 3 variables looks like. This abstraction can be very hard for students and me too.

2018-09-06 01:14:42 -0600 commented answer Plotting systems of linear equations with 3 variables

Hello, Thank you for responding. Can you point me to a resource that shows how to create a list of points. And then another resource that shows how to plot with point3d(L)?

I use SageCell.

Thank you.

2018-09-06 00:58:43 -0600 commented answer Plotting systems of linear equations with 3 variables

Hello, Thank you. That helped. What I was hoping to do was to have 3 distinct lines (or curves) rather than planes. The code did work though. I'm not familiar with viewers.

x, y, z = SR.var('x y z')
a, b, c = [2*x + 3*y - z == 15, x - 3*y + 3*z == -4, 4*x - 3*y - z == 19]
xx = (x, -10, 10)
yy = (y, -10, 10)
zz = (z, -10, 10)
pa = implicit_plot3d(a, xx, yy, zz, color='blue', alpha=0.3)
pb = implicit_plot3d(b, xx, yy, zz, color='red', alpha=0.3)
pc = implicit_plot3d(c, xx, yy, zz, color='green', alpha=0.3)
p = a + b + c
show(pa + pb + pc)
2018-09-05 02:08:16 -0600 asked a question Plotting systems of linear equations with 3 variables

Hello, Is there a way to plot these 3 equations in 3d space that would show them intersecting? 2x + 3y - z = 15, x - 3y + 3z = -4, 4x - 3y - z = 19,

I can get the numerical answers, but I'd love to be able to show a graphical representation to students and myself.

Thank you, Steve.

Here is the code for the numerical answers:

# 2*x + 3*y - z == 1
# x - 3y + 3z == - 4
# 4*x -3*y- z == 19
var('x,y,z')
words = solve([2*x + 3*y - z == 15, x - 3*y + 3*z == - 4,4*x -3*y- z == 19],x,y,z)
words
2018-06-05 23:31:59 -0600 received badge  Student (source)
2018-06-05 21:57:01 -0600 commented answer Putting the results of a function as text into a plot

Thank you very much. I really appreciate your help!

2018-06-05 07:56:56 -0600 asked a question Putting the results of a function as text into a plot

How can I put the results of functions into a plot? I can't find any examples.

f(x) = x/33.82
plotEquation = plot(f(x), -1, 70) 
equationDifferential = f.diff()(x)
big_image = plotEquation
# big_image = plotEquation + SOME CODE THAT PUTS THE RESULT OF f.diff()(x) in the plot.
big_image.show()