SOLUTION: Find the solution to the system of equation below 4x + 7y = -1 x + y = 5

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Question 858151: Find the solution to the system of equation below
4x + 7y = -1
x + y = 5
Answer by ben720(159) About Me  (Show Source):
You can put this solution on YOUR website!


multiply both sides of x+y=5 by four to get:
4x%2B4y=20
Subtract that from the first like so:
4x%2B7y=-1
-4x%2B4y=20
_______________
3y=-21
Divide both sides by 3:
y=-7
Plug that in to the second equation:
x-7=5
Add 7 to both sides:
x=12
Your answers are X=12 and Y=-7
To check, plug both into the first equation:
4%2A12%2B7%2A-7=-1
48-49=-1
-1=-1
Success!