SOLUTION: 3r-8s=-55 8r+3s=48 How do you do elimination?

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Question 478252: 3r-8s=-55
8r+3s=48
How do you do elimination?
Found 2 solutions by ewatrrr, Alan3354:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

solving by elimination

3r-8s=-55

8r+3s=48



    3r  -8s=-55

(64/3)r +8s=48*8/3 = 128  |multiplying the 2nd EQ thru by (8/3) to eliminate r

    (73/3)r = 73

        +r+=+73%2A%283%2F73%29

         r = 3  and s = 8



CHECKING our Answer

3r-8s=-55

 9 - 64 = -55

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
3r-8s=-55
8r+3s=48
How do you do elimination?
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Multiply the equations to get matching coefficients for one of the variables.
3r-8s=-55 times 3 --> 9r - 24s = -165
8r+3s=48 times 8 -->64r + 24s = 384
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9r - 24s = -165
64r +24s = 384
------------------- Add
73r = 219
r = 3
--------
Sub r into any equation and solve for s.