−8x + 4y = 24 -- (1)
−7x + 7y = 28 -- (2)
Eqn (1) & (2) are simplified as
y - 2x = 6 -- (3)
y - x = 4 -- (4)
By making y the subject of formula in (4), we have
y = x + 4 -- (5)
Substitute x + 4 for y in (3), then
x + 4 - 2x = 6
x - 2x = 6 - 4
- x = 2
x = - 2.
Substitute - 2 for x in (5), then
y = - 2 + 4
y = 2.
Therefore, (x, y) = (- 2, 2) ...Ans.
