Question

3x+2y=19 and 5x-y =18 then find x and y

Answer 1

Answer: let 3x+2y=19  ---( i )

and 5x-y =18                 ---(ii)

∴ Multiply equation (i)by 5 and (ii) by 3

∴  3x+2y = 19 X 5

∴15x + 10y = 95            ---(iii)

∴5x-y=18 -----X3

∴15x-3y=54                  ---(iv)

∴subtracting equation (iv) from (iii)

  15x + 10y = 95

-  15x -  3y   = 54

____(+)___(-)____

   0  13y     =  41

∴ y= 41/13

∴ putting this value of y in equation ( i)

∴ 3x+ 2y = 19

∴3x +2(41/13) = 19

∴ 3x + 82/13 = 19

∴ 3x = 19 X 13/82

∴ 3x= 247/82

∴3x= 3.012195

∴x =  3.012195/3

∴ x =1.004065

∴x=1.004065 and y = 41/13