How do you solve this system equation using elimination

3x +y = 23
3x - 2y = 8

please show work and the solution to the system for x, y
I have tried and tried can't seem to get it to work out.


Sagot :

3x +y = 23 this is the same as y=23-3x
3x - 2y = 8 this is the same as 3x/2-8/2=y, which gives you; y=1,5x-4
so;y=23-3xy=1,5x-4
y=y
23-3x=1,5x-4
23+4=1,5x+3x
27=4,5x
27/4,5=x
x=6
the y is:
3*6+y=23
18+y=23
y=23-18
y=5


1) 3x +y=23                           try to label them one and two.

2)3x -2y=8                          First lets find the x. To do that we have to changed the y,and find the  common number fo them.

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1) 3x+y=23            try to times the whole equation number 1) by 4, and equation 2) by 2.

2) 3x-2y=8  

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1) 12x+4y=92                That's how the euation should look after you would times it.

2) 6x-4y=16                     Then add them.    

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12x +6x = 18x      .....         4y+4y_ this won't have to be solved at we only had to times it so we could eliminate does y's as we only wanted to find out x.

92+16=108

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So then we have...

18x = 108              This means we have to divide 108 by 18 to find out x.

108/18 = 6.

x=6.

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To find y we have to do the same method but we have to eliminate x, by findin a common number in x's.

1) 3x+y=23          Try to time the two equations by 2.

2)3x-2y=8

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1) 6x+2y=46                      Yoou should get something like that.  Then add them.

2) 6x-4y=16

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6x+6x_ we won't gonna add them as we only had to multiply them to get the same answer to eliminate these.

2y+ -4y= -2y    .............   46+16=62

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So it should be:     2y=62

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No we only have to divide 62 by 2, which is 31

so y=31.