SOLUTION: Solve the following system of equations. x - y = 10 2x + y = 2 Explain which method you chose to solve the system and why you felt it was the best choice

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Question 374023: Solve the following system of equations.
x - y = 10
2x + y = 2

Explain which method you chose to solve the system and why you felt it was the best choice
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
I'LL CHOOSE THE ELIMINATION METHOD.
LEAST AMOUNT OF WORK. (11 STEPS)
x - y = 10
2x + y = 2 ADD
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3X=12
X=12/3
X=4 ANS.
4-Y=10
-Y=10-4
-Y=6
Y=-6 ANS.
PROOF:
2*4+(-6)=2
8-6=2
2=2
-----------------------
SUBSTITUTION METHOD. (15 STEPS)
X=10+Y
2(10+Y)+Y=2
20+2Y+Y=2
3Y=2-20
3Y=-18
Y=-18/6
Y=-6 ANS.
X-(-6)=10
X+6=10
X=10-6
X=4 ANS.
PROOF:
2*4+(-6)=2
8-6=2
2=2