SOLUTION: Can Someone Please show me how to solve the system by substitution method. show all steps and check the answer. x

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Question 100831: Can Someone Please show me how to solve the system by substitution method. show all steps and check the answer.
x - 2y = -1
3X + y = 4
Answer by ankor@dixie-net.com(22740) (Show Source):
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solve the system by substitution method. show all steps and check the answer.
x - 2y = -1
3x + y = 4
:
Chose one of the equation to be used for substitution.
x - 2y = -1
x = +2y - 1); added 2y to both sides to get x by itself in on the left:
:
In the 2nd equation:
3x + y = 4
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Substitute (2y-1) for x; solve for y
3(2y-1) + y = 4
:
6y - 3 + y = 4; multiplied what's inside the brackets
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7y = 4 + 3; add the y's and add 3 to both sides
:
7y = 7
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y = 7/7; divided both sides by 7
:
y = 1
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From the first equation we have x = 2y - 1, substitute 1 for y
x = 2(1) -1
x = 2 - 1
x = 1
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Check solution by substituting for x and y in the original 2nd equation:
3x + y = 4
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3(1) + 1 = 4; proves our solutions are correct.
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SOLUTION: Can Someone Please show me how to solve the system by substitution method. show all steps and check the answer. x - 2y = -1 3X + y = 4