SOLUTION: Solve the system of equations
3x + y = 1
-x + 2y = 9
The answer to this problem is a.(1, 4) or b.(-1, 4)
Some say a some say b. Can someone tell me which is the corre
Question 347200: Solve the system of equations
3x + y = 1
-x + 2y = 9
The answer to this problem is a.(1, 4) or b.(-1, 4)
Some say a some say b. Can someone tell me which is the correct answer and why? Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website! Some say a some say b.
Are you taking a poll?
There is only 1 right answer.
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You can do it two ways.
Plug the values in and see which one satisfies the equation.
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Although that works, it won't help you next time you don't have an answer to choose from.
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You can solve by elimination or substitution.
Substitution: Use 1 equation to solve for 1 variable then substitute for that variable in the second equation.
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From eq. 2,
Substitute into eq. 1,
Then from eq. 2,
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The other method is elimination.
Manipulate the equations to eliminate one of the variables.
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Multiply eq. 2 by and add the equations together.
Then use either equation to solve for .
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Isn't that better than guessing?
