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How do i work it out

 Jan 30, 2019
 #1
avatar+129852 
+2

We have this system

 

2a  + 3c   = 61

3a +  5c   = 96

 

Multiply the first equation through by 3   and the second through by -2   and we have

 

6a + 9c =    183

-6a -10c = - 192           add these

 

-c = - 9 

c = 9

 

And to find a

 

2a + 3(9) = 61

2a + 27 = 61      subtract 27 from both sides

 

2a =  34  divide both sides by 2

a = 17

 

So   (a, c)   =  (17, 9)

 

 

cool cool cool

 Jan 30, 2019

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