Transform both equations in each system of equations so that each coefficient is an integer.

***i also need it to be solved using substitution method.

For the first one multiply each term by the LCM of 4 and 6, which is 12:-

15x -36 = 2y(1)

and second multiply by 5:-

2x + y = 9(2)

solving:-
from equation (2) y = 9-2x,  substitute  in equation (1):-

15x - 36 = 2(9-2x) = 18 - 4x
19x = 54
x = 54/19 = 2.84

so y =  9 - 2(2.84) = 3.32