We see Slightly More Advanced Systems Of Equations in this video...three variable problem solving is easy. The math concepts are simple. Use the information you have to find the information you don't have. Isolate a variable and the whole thing comes into focus. Hero zero and no fun get back to one...done.
Soon he will be doing systems of equations where all three equations have all three variables and he has to eliminate to solve them but we aren't there yet; however, this is where we are going:
3x + 2y + 4z = 9
-x + 3y + 2z = 1
4x - 5y - z = 3
For now he is doing problems like this:
L + T +3D = 8
T + 3D = 14
L + 2D = 0
There are a lot of intermediary steps between those two sets of problems. Steps that are ENTIRELY ABSENT in modern day text books. Now they give you three or four examples a few rules and some process and "off you go...and hey graph it while you're at it even though this is your first exposure to a "Z" axis."
Here are several vids strung together with my poor (but improving) editing skills:
For those pressed for time here is a short video covering just the one problem shown above:
To see how we started off and why I'm using L, T and D check out this post Simple Systems Of Equations.
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