SOLUTION: How would you do Subsituion method for 4x=720-3y and 5y=12x?

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Question 314969: How would you do Subsituion method for 4x=720-3y and 5y=12x?
Found 3 solutions by Fombitz, malaydassharma, solver91311:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.4x=720-3y+
2.5y=12x
Multiply eq. 1 by 3,
12x=2160-9y
Substitute this into eq. 2 directly,
5y=2160-9y
14y=2160
y=2160%2F14
highlight%28y=1080%2F7%29
Then from eq. 2,
5y=12x
x=%285%2F12%29y
x=%281080%2F7%29%285%2F12%29
highlight%28x=450%2F7%29

Answer by malaydassharma(59) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Linear System solver (using determinant)
Solve:
+system%28+%0D%0A++++4%5Cx+%2B+3%5Cy+=+720%2C%0D%0A++++-12%5Cx+%2B+5%5Cy+=+0+%29%0D%0A++

Any system of equations:


has solution

or



(x=64.2857142857143, y=154.285714285714}

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


I would divide both sides of the second equation by 5 and substitute the resulting expression in x for y in the first equation.

Something like this:



And then I would solve for . As soon as I had a value for I would substitute that back into either of the original equations so that I could solve for . But then again, that's just me. Someone else might do it differently. There are several other valid ways.


John