SOLUTION: The solution to the system of equations: x + 3y = 12 4x - y = -17

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Question 147794: The solution to the system of equations:
x + 3y = 12
4x - y = -17

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%2B3y=12
2.4x-y=-17
You didn't specify a method.
We'll use substitution.
Solve eq.1 for x in terms of y.
1.x%2B3y=12
x=12-3y
Now substitute this into eq. 2 and solve for y.
2.4x-y=-17
4%2812-3y%29-y=-17
48-12y-y=-17
48-13y=-17
-13y=-65
y=5
From eq. 1,
x=12-3y
x=12-3%285%29
x=12-15
x=-3
The solution is x=-3 and y=5, also shown graphically.
+graph%28+300%2C+300%2C+-5%2C+5%2C+-2%2C+8%2C+4x%2B17%2C+%2812-x%29%2F3%29+