System solving 2x-4y = 12    x+3y = 3

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You can use substitution to solve the system of equations

2x - 4y = 12 ...(1)

x + 3y = 3 ...(2)

From (2), x + 3y = 3

=> x = 3 - 3y

Substitute this in (1)

2*(3 - 3y) - 4y = 12

=> 6 - 6y...

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You can use substitution to solve the system of equations

2x - 4y = 12 ...(1)

x + 3y = 3 ...(2)

From (2), x + 3y = 3

=> x = 3 - 3y

Substitute this in (1)

2*(3 - 3y) - 4y = 12

=> 6 - 6y - 4y = 12

=> 6 - 10y = 12

=> 10y = -6

=> y = -6/10

x = 3 - 3y = 3 + 3*(6/10) = 3 + 18/10

=> x = 48/10

The solution of the system of equations is x = 48/10 and y = -6/10

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First, find a value for x using the second equation:

x = 3 - 3y

Then substitute that in to the first equation

2 (3-3y) - 4y = 12

6 - 6y - 4y = 12

- 10y = 6

y = -.6

Then you plug this back into the first equation

x + 3*-.6 = 3

x - 1.8 = 3

x = 4.8

So, x = 4.8 and y = -.6

Approved by eNotes Editorial Team