SOLUTION: Solve each system by elimination. 3x- y=7 and 2x+y=3

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Question 709656: Solve each system by elimination. 3x- y=7 and 2x+y=3
Answer by lenny460(1073) About Me  (Show Source):
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Solve each system by elimination. 3x- y=7 and 2x+y=3

3x - y = 7
2x + y = 3
3x - y + 2x + y = 7 + 3
Combine like terms:
3x + 2x = 5x
-y + y = 0
7 + 3 = 10
5x = 10
Divide each side by 5
5x/5 = 10/5
x = 2


Substitute x = 2 in equation 1.
3x - y = 7
3(2) - y = 7
6 - y = 7
Subtract 6 from each side.
6 - y - 6 = 7 - 6
6 - 6 = 0
7 - 6 = 1
-y = 1
Divide each side by -1
-1y/-1 = 1/-1
y = -1

2x + y = 3
2()2 + -1 = 3
4 + -1 = 3 or
4 - 1 = 3

Therefore:
x = 2 and
y = -1





Lennox Obuong
Algebra Tutor