Question

how to do it by elimination process





class 10 RS Agarwal :real number​

Answer 1

take LCM

x/2 - y/9 = 6  ...............[1]

x/7 + y/3 = 5 ...............[2]

gives,

18x - 18y =6

    18

18x - 18y = 108 ...........[3]

21x + 21y =5

    21

21x + 21y =105...............[4]

adding [3] - [4] {symbol varies means we want to subtract}

we get,

-3x - 39y = 3

-3x = 3 + 39y

x = 3+39y  

       -3