what is the system of equation of 3x+2y=7 and x+2y=1

Question

Im In The USA

Answer 1

3x + 2y = 7

x + 2y = 1

 

Both equations contain a 2y term, so let's try eliminating it.  Multiply the second equation by -1 so it becomes -x - 2y = -1.  Now add it to the first equation:

 

3x + 2y =  7

-x  - 2y = -1

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2x +  0  = 6

 

2x = 6

 

x = 3

 

To find y, plug x=3 into either equation

 

x + 2y = 1

3 + 2y = 1

2y = -2

 

y = -1

 

CHECK:

3x + 2y = 7

3(3) + 2(-1) = 7

9 -2 = 7

7 = 7      CHECK!

 

x + 2y = 1

3 + 2(-1) = 1

3 - 2 = 1

1 = 1      CHECK!