Answer:
Y is the appropriate variable and the most easiest and convenient to eliminate
name 2x + y = 7 as equation i
and 3/2 x - y = 7/2 as equation ii
then add equation i and ii together
(3/2 + 2) x + y - y = (7 + 7/2)
(7/2) x = (21/2)
x = 3
then put in x = 3 in equation i
4 + y = 7
x = 7 - 4
x = 3
Therefore x = 3 and y = 3