SOLUTION: What is the substition method for 18x+6y=78, 12x+54y=-48?

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Question 409504: What is the substition method for 18x+6y=78, 12x+54y=-48?
Found 2 solutions by MathLover1, stanbon:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

18x%2B6y=78
12x%2B54y=-48

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++18%5Cx+%2B+6%5Cy+=+78%2C%0D%0A++++12%5Cx+%2B+54%5Cy+=+-48+%29%0D%0A++We'll use substitution. After moving 6*y to the right, we get:
18%2Ax+=+78+-+6%2Ay, or x+=+78%2F18+-+6%2Ay%2F18. Substitute that
into another equation:
12%2A%2878%2F18+-+6%2Ay%2F18%29+%2B+54%5Cy+=+-48 and simplify: So, we know that y=-2. Since x+=+78%2F18+-+6%2Ay%2F18, x=5.

Answer: system%28+x=5%2C+y=-2+%29.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What is the substition method for
18x+6y = 78
12x+54y=-48
-----------------
3x+ y = 13
2x+9y = -8
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27x + 9y = 9*13
2x + 9y = -8
-----------------
Subtract and solve for "y":
25x = 125
x = 5
-----
Solve for "x":
3x + y = 13
3*5 + y = 13
y = -2
--------
Cheers,
Stan H.
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