Question

determine x e y sabendo que 2x+5y=17 e x-y=5

Answer 1

x-y= 5
x= y + 5

2(y + 5) + 5y = 17

2y + 10 + 5y = 17

7y = 7

y = 1

x-y = 5

x - 1 = 5

x = 4

Answer 2

2x+5y=17
x-y=5(-2)

2x+5y=17
-2x+2y=-10

7y=7
y=7/7=1
 
*x-y=5
 x-1=5
 x=6