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-5x-y=12

x+y=4

-6x+9y=11

User Catdotgif
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1 Answer

12 votes
12 votes

Answer:

1. x = -12+y / 5 , y = -12-5x

2. x = 4 - y , y = 4 - x

3. x = -11 - 9y / 6 , y = 11 + 6x / 9

( for the numbers in fractions such as the x value for #1 and x & y value for #3, put the negative sign in front of the fraction, not the number okay? )

Explanation:

  • -5x - y = 12

---> -5x - y = 12 -5x - y = 12

= -5x - y = 12 = +5x +5x

+y +y ---------------------

--------------------- -y = 12 + 5x

-5x = 12 + y /-1 /-1

/-5 /-5 ----------------------

--------------------- y = -12-5x

x = -12+y / 5

-------------------------------------------------------------------------------------------

  • x + y = 4

---> x + y = 4 x + y = 4

= -y -y = -x -x

--------------------- ----------------

x = 4 - y y = 4 - x

--------------------------------------------------------------------------------------------

  • -6x + 9y = 11

-----> -6x + 9y = 11 -6x + 9y = 11

= -9y -9y = +6x +6x

------------------------------ ------------------------

-6x = 11 - 9y 9y = 11 + 6x

/-6 /-6 /9 /9

------------------------------- --------------------------

x = -11 - 9y / 6 y = 11 + 6x / 9

User Prathap Badavath
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