Answer:
(3, - 6 )
Explanation:
x - 2y = 15 ( add 2y to both sides )
x = 2y + 15 → (1)
2x + 4y = - 18 → (2)
substitute x = 2y + 15 into (2)
2(2y + 15) + 4y = - 18 ← distribute parenthesis and simplify left side
4y + 30 + 4y = - 18
8y + 30 = - 18 ( subtract 30 from both sides )
8y = - 48 ( divide both sides by 8 )
y = - 6
substitute y = - 6 into (1)
x = 2(- 6) + 15 = - 12 + 15 = 3
solution is (3, - 6 )