Respuesta :
Answer:
(7, - 2 )
Step-by-step explanation:
x - y = 9 ( add y to both sides )
x = y + 9 → (1)
2x + 5y = 4 → (2)
Substitute x = y + 9 into (2)
2(y + 9) + 5y = 4 ← distribute parenthesis and simplify left side
2y + 18 + 5y = 4
7y + 18 = 4 ( subtract 18 from both sides )
7y = - 14 ( divide both sides by 7 )
y = - 2
Substitute y = - 2 into (1)
x = - 2 + 9 = 7
solution is (7, - 2 )
