Respuesta :

Answer:

5/2 OR 2.5

Step-by-step explanation:

( x + 2y ) = 7 , ( x - 2y ) = 5

x = 7 - 2y , x = 5 + 2y

substitute the two eqns together:

7 - 2y = 5 + 2y

7 - 5 = 2y + 2y

2 = 4y

y = 1/2

when y = 1/2 ,

5y = 5(1/2)

= 5/2 OR 2.5