SOLUTION: solve by the substitution method and then two ordered pairs! 9x-9y=-9 3x+13=y

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Question 259887: solve by the substitution method and then two ordered pairs!
9x-9y=-9
3x+13=y

Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
solve by the substitution method and then two ordered pairs!
9x-9y=-9 --> 3x-3y = -3 --> 3x = 3y-3
3x+13=y
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Sub for 3x into the 2nd eqn
3y-3 + 13 = y
3y+10 = y
2y = -10
y = -5
x = -6
--------
The only ordered pair of the solution is (-6,-5)
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PS Most people would have subbed for y into the 1st eqn, but that's not the only way to do it.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve by the substitution method and then two ordered pairs!
9x-9y=-9
3x+13=y
---------------
Simplify the 1st equation:
x - y = -1
----
Substitute for "y" in this equation and solve for "x":
x - (3x+13) = -1
x - 3x - 13 = -1
-2x = 12
x = -6
---
Substitute into x-y = -1 to solve for "y":
-6 - y = -1
y = -5
==========================
Solution:
x = -6, y = -5
===============================
9x-9y=-9
3x+13=y
----------------
x-y = -1
3x+13 = y
--------------
y = x+1
y = 3x+13
--------------
graph%28400%2C300%2C-10%2C10%2C-10%2C30%2Cx%2B1%2C3x%2B13%29
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Cheers,
Stan H.