solve the simultaneous equations: 3x + 5y = 4 ; 7x - 3y = 8

first recognise that if you double the first equation the both equations will be equal to 8.so now we have 6x + 10y = 8 ; 7x - 3y = 8now we can set the equations equal to each other to get 6x + 10y = 7x - 3yby rearranging for x we get:x = 13ynow substituting this into the first orignal equation we get:3(13y) + 5y = 4 so,39y + 5y = 4 so,44y = 4 so,y= 1/11then substtuting this value into x = 13y we get x = 13/11 ; y=1/11

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