Answer:
x = 5, y = -2/3
Explanation:
4x+3y=18 .......make x the subject
4x = 18 - 3y
x = (18 - 3y )/4 ......equation 1
x-3y=7 ......make x the subject, follow the same method
x = 7 + 3y ......equation 2
then solve them ( equation1 and equation2 ) simultaneously:
7 + 3y = (18 - 3y )/4
( 7 + 3y ) * 4 = 18 - 3y
28 + 12y = 18 - 3y ........bring y in one side and numbers in another side
10 = - 15 y
y = - 2/3
if y = -2/3
then x = 7 + 3 ( -2/3 ) .....from equation 2
x = 7 - 2
x = 5